Generational change for digital technologies are rapid and disruptive. ‘In the digital context the next generation may only be five to ten years away!’ Tom Gollins from the National Archives reminds us, and this seems like a fairly conservative estimate.
It can feel like the rate of change is continually accelerating, with new products appearing all the time. It is claimed, for example, that the phenomena of ‘wearable tech chic’ is now upon us, with the announcement this week that Google’s glass is available to buy for £1,000.
The impact of digital technologies have been felt throughout society, and this issue will be explored in a large immersive exhibition of art, design, film, music and videogames held at the Barbian July-Sept 2014. It is boldly and emphatically titled: Digital Revolution.
To bring such technological transformations back into focus with our work at Greatbear, consider this 2004 brochure that recently re-surfaced in our Studio. As an example of the rapid rate of technological change, you need look no further.
Storage media such as Zip disks, Jaz Cart, Exabytes and hard drives that could store between 36-500Gb of data were also available to purchase.
RMGI are currently the only manufacturer of professional open reel audio tape. In the 2004 catalogue, different brands of open reel analogue tape are listed at a third of 2014 retail prices, taking into account rates of inflation.
While some of the products included in the catalogue, namely CDs, DVDs and open reel tape, have maintained a degree of market resiliency due to practicality, utility or novelty, many have been swept aside in the march of technological progress that is both endemic and epidemic in the 21st century.
We work with a range of customers at Greatbear, digitising anything from personal collections to the content of institutional archives. Because of this, what customers need from a digitisation service can be very different.
A key issue relates to the question of how much we process the digital file, both as part of the transfer and in post-production. In other words, to what extent do we make alterations to the form of the recording when it becomes a digitised artifact. While this may seem like an innocuous problem, the question of whether or not to apply processing, and therefore radically transform the original recording, is a fraught, and for some people, ethical, consideration.
There are times when applying processing technologies is desirable and appropriate. With the transfer of video tape, for example, we always use time-based correctors or frame synchronisers to reduce or eliminate errors during play back. Some better quality video tape machines, such as the U-matic BVU-950P, already have time-based correctors built in which makes external processing unnecessary. As the AV Artifact Atlas explains however, time-based correction errors are very common with video tape:
‘When a different VTR is used to playback the same signal, there can be slight mechanical and electronic differences that prevent the tape from being read in the same way it was written. Perhaps the motors driving the tape in a playback VTR move slightly slower than they did in the camera that recorded the tape, or maybe the head of the playback VTR rotates a fraction quicker than the video head in the machine that recorded the tape. These tiny changes in timing can dramatically affect stability in a video image.’
We also utilise built in processes that are part of machine’s circuitry, such as drop out compensation and noise reduction. We use these, however, not in order to make the tape ‘look better.’ We do it rather as a standard calibration set up, which is necessary for the successful playback of the tape in a manner appropriate to its original operating environment.
After all, video tape machines were designed to be interchangeable. It is likely such stabilising processing would have been regularly used to play back tapes in machines that were different to those they were recorded on. Time-based correction and frame synchronisation are therefore integral to the machine/ playback circuitry, and using such processing tools is central to how we successfully migrate tape-based collections to digital files.
Digital processing tools
Our visual environment has changed dramatically since the days when domestic video tape was first introduced, let alone since the hay day of VHS. The only certainty is that it will continue to change. Once it was acceptable for images to be a bit grainy and low resolution, now only the crisp clarity of a 4K Ultra HD image will do. There is perhaps the assumption that ‘clearer is better’, that being able to watch moving images in minute detail is a marker of progress. Yet should this principle be applied to the kinds of digitisation work we do at Great Bear? There are processors that can transform the questionable analogue image into a bright, high definition, colour enriched digital copy. The teranex processor, for example, ‘includes extremely high quality de-interlacing, up conversion, down conversion, SD and HD cross/standards conversion, automatic cadence detection and removal even with edited content, noise reduction, adjustable scaling and aspect ratio conversion.’ ‘Upgrading’ analogue images in this way does come with certain ethical risks.
Talking about ethics in conjunction with video or audio tape might seem a bit melodramatic, but it is at the point of intervention/ non-intervention where the needs of our customers diverge the most. This is not to say that people who do want to process their tapes are unethical – far from it! We understand that for some customers it may be preferable for such processing to occur, or to apply other editing techniques such as noise reduction or amplification, so that audio can be heard with greater clarity.
Instead we want to emphasise that our priority is getting the best out of the tape and our playback machines, rather than relying on the latest processing technology that is also at risk from obsolescence. After all, a heavily processed file will always require further processing at an unknown point in future so that it can maintain visually relevant to whatever format is commercially dominant at the time. Such transformations of the digital file, which are necessarily destructive and permanent, contribute to the further circulation of what Hito Steyerl calls ‘poor images‘, ‘a rag or a rip; an AVI or a JPEG…The poor image has been uploaded, downloaded, shared, reformatted, and reedited. It transforms quality into accessibility, exhibition value into cult value, films into clips, contemplation into distraction.’
Maintaining the integrity, and as far as possible authenticity of the original recordings, is a core part of our methodology. In this way our approach corresponds with Jisc’s mantra of ‘reproduction not optimisation’ where they write:
‘Improving, altering or modifying media for optimisation may seem logical when presenting works to a public or maintaining perceived consistency. It should be remembered that following an often natural inclination to enhance what we perceive to be a poor level of quality is a subjective process prescribed by personal preference, technological trends and cultural influences. In many cases the intentions of a creator are likely to be unknown and this can cause difficulties in interpreting levels of quality. In these instances common sense alongside trepidation should prevail. On the one end of the spectrum unintelligible recordings may be of little use to anyone, whereas at the opposite end recordings from previous eras were not produced with modern standards of clarity in mind.’
It is important to bear in mind, however, that even if a file is subject to destructive editing there may come a time when the metadata created about the artefact can help to illuminate its context and provenance, and therefore help it maintain its authenticity. The debates regarding digital authenticity and archiving will of course shift as time passes and practices evolve.
In the meantime, we will continue to do what we are most skilled at: restoring, repairing and migrating magnetic tape to digital files in a manner that maintains both the integrity of the original operating environment and the recorded signal.
‘there is consensus internationally that we as archivists have a 10-20 year window of opportunity in which to migrate the content of our physical sound collections to stable digital files. After the end of this 10-20 year window, general consensus is that the risks faced by physical media mean that migration will either become impossible or partial or just too expensive.’
This point of view certainly corresponds to our experience at Greatbear. As collectors of a range of domestic and professional video and audio tape playback machines, we are aware of the particular problems posed by machine obsolescence. Replacement parts can be hard to come by, and the engineering expertise needed to fix machines is becoming esoteric wisdom. Tape degradation is of course a problem too. These combined factors influence the shortened horizon of magnetic tape-based media.
IRENE (Image, Reconstruct, Erase Noise, Etc.), developed by physicist Carl Haber at the Lawrence Berkeley National Laboratory, is a software programme that ‘photographs the grooves in fragile or decayed recordings, stitches the “sounds” together with software into an unblemished image file, and reconstructs the “untouchable” recording by converting the images into an audio file.’
The programme was developed by Haber after he heard a radio show discuss the Library of Congress’ audio collections that were so fragile they risked destruction if played back. Haber speculated that the insights gained from a project he was working on could be used to recover these audio recordings. ‘“We were measuring silicon, why couldn’t we measure the surface of a record? The grooves at every point and amplitude on a cylinder or disc could be mapped with our digital imaging suite, then converted to sound.”’
For those involved in the development of IRENE, there was a strong emphasis on the benefits of patience and placing trust in the inevitable restorative power of technology. ‘It’s ironic that as we put more time between us and the history we are exploring, technology allows us to learn more than if we had acted earlier.’
Can such a hands-off approach be applied to magnetic tape based media? Is the 10-20 year window of opportunity described by Tovell above unnecessarily short? After all, it is still possible to playback wax cylinder recordings from the early 20th century which seem to survive well over long periods of time, and magnetic tape is far more durable than is commonly perceived.
In a fascinating audio recording made for the Pitt Rivers Museum in Oxford, Nigel Bewley from the British Library describes how he migrated wax cylinder recordings that were made by Evans Pritchard in 1928-1930 and Diamond Jenness in 1911-1912. Although Bewley reveals his frustration in the preparation process, he reveals that once he had established the size of stylus and rotational speed of the cylinder player, the transfer was relatively straightforward.
You will note that in contrast with the recovery work made possible by IRENE, the cylinder transfer was made using an appropriate playback mechanism, examples of which can accessed on this amazing section of the British Library’s website (here you can also browse through images and information about disc cutters, magnetic recorders, radios, record players, CD players and accessories such as needle tins and headphones – a bit of a treasure trove for those inclined toward media archaeology).
Perhaps the development of the IRENE technology will mean that it will no longer be necessary to use such ‘authentic’ playback mechanisms to recover information stored on obsolete media. This brings us neatly to the question of emulation.
Emulation
If we assume that all the machines that play back magnetic tape become irrevocably obsolete in 10-20 years, what other potential extraction methods may be available? Is it possible that emulation techniques, commonly used in the preservation of born-digital environments, can be applied to recover the recorded information stored on magnetic tape?
‘Emulation is a concept in digital preservation to keep things, especially hardware architectures, as they were. As the hardware itself might not be preservable as a physical entity it could be very well preserved in its software reproduction. […] For memory institutions old digital artifacts become more easy to handle. They can be viewed, rendered and interacted-with in their original environments and do not need to be adapted to our modern ones, saving the risk of modifying some of the artifact’s significant properties in an unwanted way. Instead of trying to mass-migrate every object in the institution’s holdings, objects are to be handled on access request only, significantly shifting the preservation efforts.’
For the sake of speculation, let us imagine we are future archaeologists and consider some of the issues that may arise when seeking to emulate the operating environments of analogue-based tape media.
To begin with, without a working transport mechanism which facilitates the transmission of information, the emulation of analogue environments will need to establish a circuitry that can process the Radio Frequency (RF) signals recorded on magnetic tape. As Jonathan Sterne reflects, ‘if […] we say we have to preserve all aspects of the platform in order to get at the historicity of the media practice, that means archival practice will have to have a whole new engineering dimension to it.’
Yet with the emulation of analogue environments, engineering may have to be a practical consideration rather than an archival one. For example, some kind of transport mechanism would presumably have to be emulated through which the tape could be passed through. It would be tricky to lay the tape out flat and take samples of information from its surface, as IRENE’s software does to grooved media, because of the sheer length of tape when it unwound. Without an emulated transport mechanism, recovery would be time consuming and therefore costly, a point that Tovell intimates at the beginning of the article. Furthermore, added time and costs would necessitate even more complex selection and appraisal decisions on behalf of archivists managing in-operative magnetic tape-based collections. Questions about value will become fraught and most probably politically loaded. With an emulated transport mechanism, issues such as tape vulnerability and head clogs, which of course impact on current migration practices, would come into play.
Audio and video differences
On a technical level emulation may be vastly more achievable for audio where the signal is recorded using a longitudinal method and plays back via a relatively simple process. Audio tape is also far less propriety than video tape. On the SONY APR-5003V machine we use in the Greatbear Studio for example, it is possible to play back tapes of different sizes, speeds, brands, and track formations via adjustments of the playback heads. Such versatility would of course need to be replicated in any emulation environment.
The technical circuitry for playing back video tape, however, poses significantly more problems. Alongside the helical scan methods, which records images diagonally across the video tape in order to prevent the appearance of visible joints between the signal segments, there are several heads used to read the components of the video signal: the image (video), audio and control (synch) track.
Unlike audio, video tape circuitry is more propriety and therefore far less inter-operable. You can’t play a VHS tape on a U-Matic machine, for example. Numerous mechanical infrastructures would therefore need to be devised which correspond with the relevant operating environments – one size fits all would (presumably) not be possible.
A generic emulated analogue video tape circuit may be created, but this would only capture part of the recorded signal (which, as we have explored elsewhere on the blog, may be all we can hope for in the transmission process). If such systems are to be developed it is surely imperative that action is taken now while hardware is operative and living knowledge can be drawn upon in order to construct emulated environments in the most accurate form possible.
While hope may rest in technology’s infinite capacity to take care of itself in the end, excavating information stored on magnetic tape presents far more significant challenges when compared with recordings on grooved media. There is far more to tape’s analogue (and digital) circuit than a needle oscillating against a grooved inscription on wax, lacquer or vinyl.
The latter part of this article has of course been purely speculative. It would be fascinating to learn about projects attempting to emulate the analogue environment in software – please let us know if you are involved in anything in the comments below.
Is this the end of tape as we know it? Maybe not quite yet, but October 1, 2014, will be a watershed moment in professional media production in the UK: it is the date that file format delivery will finally ‘go tape-less.’
Establishing end-to-end digital production will cut out what is now seen as the cumbersome use of video tape in file delivery. Using tape essentially adds a layer of media activity to a process that is predominantly file based anyway. As Mark Harrison, Chair of the Digital Production Partnership (DPP), reflects:
Example of a workflow for the DPP AS-11 standard
‘Producers are already shooting their programmes on tapeless cameras, and shaping them in tapeless post production environments. But then a strange thing happens. At the moment a programme is finished it is transferred from computer file to videotape for delivery to the broadcaster. When the broadcaster receives the tape they pass it to their playout provider, who transfers the tape back into a file for distribution to the audience.’
Founded in 2010, the DPP are a ‘not-for-profit partnership funded and led by the BBC, ITV and Channel 4 with representation from Sky, Channel 5, S4/C, UKTV and BT Sport.’ The purpose of the coalition is to help ‘speed the transition to fully digital production and distribution in UK television’ by establishing technical and metadata standards across the industry.
The transition to a standardised, tape-less environment has further been rationalised as a way to minimise confusion among media producers and help economise costs for the industry. As reported on Avid Blogs production companies, who often have to respond to rapidly evolving technological environments, are frantically preparing for deadline day. ‘It’s the biggest challenge since the switch to HD’, said Andy Briers, from Crow TV. Moreover, this challenge is as much financial as it is technical: ‘leading post houses predict that the costs of implementing AS-11 delivery will probably be more than the cost of HDCAM SR tape, the current standard delivery format’, writes David Wood on televisual.com.
Outlining the standard
Audio post production should now be mixed to the EBU R128 loudness standard. As stated in the DPP’s producer’s guide, this new audio standard ‘attempts to model the way our brains perceive sound: our perception is influenced by frequency and duration of sound’ (9).
In addition, the following specifications must be observed to ensure the delivery format is ‘technically legal.’
HD 1920×1080 in an aspect ratio of 16:9 (1080i/25)
Photo Sensitive Epilepsy (flashing) testing to OFCOM standard/ the Harding Test
The shift to file-based delivery will require new kinds of vigilance and attention to detail in order to manage the specific problems that will potentially arise. The DPP producer’s guide states: ‘unlike the tape world (where there may be only one copy of the tape) a file can be copied, resulting in more than one essence of that file residing on a number of servers within a playout facility, so it is even more crucial in file-based workflows that any redelivered file changes version or number’.
Another big development within the standard is the important role performed by metadata, both structural (inherent to the file) and descriptive (added during the course of making the programme) . While broadcasters may be used to manually writing metadata as descriptive information on tape-boxes, they must now be added to the digital file itself. Furthermore, ‘the descriptive and technical metadata will be wrapped with the video and audio into a new and final AS-11 DPP MXF file,’ and if ‘any changes to the file are [made it is] likely to invalidate the metadata and cause the file to be rejected. If any metadata needs to be altered this will involve re-wrapping the file.’
Interoperability: the promise of digital technologies
The sector-wide agreement and implementation of digital file-delivery standards are significant because they represent a commitment to manufacturing full interoperability, an inherent potential of digital technologies. As French philosopher of technology Bernard Stiegler explains:
‘The digital is above all a process of generalised formalisation. This process, which resides in the protocols that enable interoperability, makes a range of diverse and varied techniques. This is a process of unification through binary code of norms and procedures that today allow the formalisation of almost everything: traveling in my car with a GPS system, I am connected through a digitised triangulation process that formalises my relationship with the maps through which I navigate and that transform my relationship with territory. My relationships with space, mobility and my vehicle are totally transformed. My inter-individual, social, familial, scholarly, national, commercial and scientific relationships are all literally unsettled by the technologies of social engineering. It is at once money and many other things – in particular all scientific practices and the diverse forms of public life.’
This systemic homogenisation described by Stiegler is called into question if we consider whether the promise of interoperability – understood here as different technical systems operating efficiently together – has ever been fully realised by the current generation of digital technologies. If this was the case then initiatives like the DPP’s would never have to be pursued in the first place – all kinds of technical operations would run in a smooth, synchronous matter. Amid the generalised formalisation there are many micro-glitches and incompatibilities that slow operations down at best, and grind them to a halt at worst.
With this in mind we should note that standards established by the DPP are not fully interoperable internationally. While the DPP’s technical and metadata standards were developed in close alliance with the US-based Advanced Media Workflow Association’s (AMWA) recently released AS-11 specification, there are also key differences.
As reported in 2012 by Broadcast Now Kevin Burrows, DPP Technical Standards Lead, said: ‘[The DPP standards] have a shim that can constrain some parameters for different uses; we don’t support Dolby E in the UK, although the [AMWA] standard allows it. Another difference is the format – 720 is not something we’d want as we’re standardising on 1080i. US timecode is different, and audio tracks are referenced as an EBU standard.’ Like NTSC and PAL video/ DVD then, the technical standards in the UK differ from those used in the US. We arguably need, therefore, to think about the interoperability of particular technical localities rather than make claims about the generalised formalisation of all technical systems. Dis-synchrony and technical differences remain despite standardisation.
The AmberFin Academy blog have also explored what they describe as the ‘interoperability dilemma’. They suggest that the DPP’s careful planning mean their standards are likely to function in an efficient manner: ‘By tightly constraining the wrapper, video codecs, audio codecs and metadata schema, the DPP Technical Standards Group has created a format that has a much smaller test matrix and therefore a better chance of success. Everything in the DPP File Delivery Specification references a well defined, open standard and therefore, in theory, conformance to those standards and specification should equate to complete interoperability between vendors, systems and facilities.’ They do however offer these words of caution about user interpretation: ‘despite the best efforts of the people who actually write the standards and specifications, there are areas that are, and will always be, open to some interpretation by those implementing the standards, and it is unlikely that any two implementations will be exactly the same. This may lead to interoperability issues.’
It is clear that there is no one simple answer to the dilemma of interoperability and its implementation. Establishing a legal commitment, and a firm deadline date for the transition, is however a strong message that there is no turning back. Establishing the standard may also lead to a certain amount of technological stability, comparable to the development of the EIAJ video tape standards in 1969, the first standardised format for industrial/non-broadcast video tape recording. Amid these changes in professional broadcast standards, the increasingly loud call for standardisation among digital preservationists should also be acknowledged.
For analogue and digital tapes however, it may well signal the beginning of an accelerated end. The professional broadcast transition to ‘full-digital’ is a clear indication of tape’s obsolescence and vulnerability as an operable media format.
If you work in digital preservation then the term ‘significant properties’ will no doubt be familiar to you. The concept has been viewed as a hindrance due to being shrouded by foggy terminology, as well as a distinct impossibility because of the diversity of digital objects in the world which, like their analogue counterparts, cannot be universally generalised or reduced to a series of measurable characteristics.
In a technical sense, establishing a set of core characteristics for file formats has been important for initiatives like Archivematica, ‘a free and open-source digital preservation system that is designed to maintain standards-based, long-term access to collections of digital objects.’ Archivematica implement ‘default format policies based on an analysis of the significant characteristics of file formats.’ These systems manage digital information using an ‘agile software development methodology’ which ‘is focused on rapid, iterative release cycles, each of which improves upon the system’s architecture, requirements, tools, documentation, and development resources.’
Such a philosophy may elicit groans of frustration from information managers who may well want to leave their digital collections alone, and practice a culture of non-intervention. Yet this adaptive-style of project management, which is designed to respond rapidly to change, is often contrasted with predictive development that focuses on risk assessment and the planning of long-term projects. The argument against predictive methodologies is that, as a management model, it can be unwieldy and unresponsive to change. This can have damaging financial consequences, particularly when investing in expensive, risky and large scale digital preservation projects, as the BBC’s failed DMI initiative demonstrates.
Indeed, agile software development methodology may well be an important key to the sustainability of digital preservation systems which need to find practical ways of maneuvering technological innovations and the culture of perpetual upgrade. Agility in this context is synonymous with resilience, and the practical application of significant properties as a means to align file format interoperability offers a welcome anchor for a technological environment structured by persistent change.
Significant properties vs the authentic digital object
What significant properties imply, as archival concept and practice, is that desiring authenticity for the digitised and born-digital objects we create is likely to end in frustration. Simply put, preserving all the information that makes up a digital object is a hugely complex affair, and is a procedure that will require numerous and context-specific technical infrastructures.
As Trevor Owens explains: ‘you can’t just “preserve it” because the essence of what matters about “it” is something that is contextually dependent on the way of being and seeing in the world that you have decided to privilege.’ Owens uses the example of the Geocites web archiving project to demonstrate that if you don’t have the correct, let’s say ‘authentic’ tools to interpret a digital object (in this case, a website that is only discernible on certain browsers), you simply cannot see the information accurately. Part of the signal is always missing, even if something ‘significant’ remains (the text or parts of the graphics).
It may be desirable ‘to preserve all aspects of the platform in order to get at the historicity of the media practice’, Jonathan Sterne, author of MP3: Meaning of a Format suggests, but in a world that constantly displaces old technological knowledge with new, settling for the preservation of significant properties may be a pragmatic rather than ideal solution.
Analogue to digital issues
To bring these issues back to the tape we work we with at Great Bear, there are of course times when it is important to use the appropriate hardware to play the tapes back, and there is a certain amount of historically specific technical knowledge required to make the machines work in the first place. We often wonder what will happen to the specialised knowledge learnt by media engineers in the 70s, 80s and 90s, who operated tape machines that are now obsolete. There is the risk that when those people die, the knowledge will die with them. Of course it is possible to get hold of operating manuals, but this is by no means a guarantee that the mechanical techniques will be understood within a historical context that is increasingly tape-less and software-based. By keeping our wide selection of audio and video tape machines purring, we are sustaining a machinic-industrial folk knowledge which ultimately helps to keep our customer’s magnetic tape-based, media memories, alive.
Of course a certain degree of historical accuracy is required in the transfers because, very obviously, you can’t play a V2000 tape on a VHS machine, no matter how hard you try!
Yet the need to play back tapes on exactly the same machine becomes less important in instances where the original tape was recorded on a domestic reel-to-reel recorder, such as the Grundig TK series, which may not have been of the greatest quality in the first place. To get the best digital transfer it is desirable to play back tapes on a machine with higher specifications that can read the magnetic information on the tape as fully as possible. This is because you don’t want to add any more errors to the tape in the transfer process by playing it back on a lower quality machine, which would then of course become part of the digitised signal.
It is actually very difficult to remove things like wow and flutterafter a tape has been digitised, so it is far better to ensure machines are calibrated appropriately before the tape is migrated, even if the tape was not originally recorded on a machine with professional specifications. What is ultimately at stake in transferring analogue tape to digital formats is the quality of the signal. Absolute authenticity is incidental here, particularly if things sound bad.
The moral of this story, if there can be one, is that with any act of transmission, the recorded signal is liable to change. These can be slight alterations or huge drop-outs and everything in-between. The agile software developers know that given the technological conditions in which current knowledge is produced and preserved, transformation is inevitable and must be responded to. Perhaps it is realistic to assume this is the norm in society today, and creating digital preservation systems that are adaptive is key to the survival of information, as well as accepting that preserving the ‘full picture’ cannot always be guaranteed.
The Women’s Liberation Movement (WLM) is full of quirky examples of how womyn tried to wrestle culture from the sordid grip of male domination.
Part of this process was reinventing the world in wimmin’s image, word and song; to create and reclaim a lasting herstory in which sisterhood could flourish.
A recent U-Matic video tape transferconducted in the Greatbear studio offers a window into this cultural heritage.
State Your Destination was a film made by Bristol-based ’80s feminist film collective Women in Moving Pictures (W.I.M.P.S.), whose complete archive is stored at the Feminist Archive South.
The way women shirked the language of patriarchy is evident on the tape box. We digitised the ‘MISTRESS’ copy, not the master copy.
Seeing the mistress copy today is a reminder of the way gendered language influences how we can think about cultural forms. The master copy, of course, in conventional understanding, is the finished article, the final cut. The master of the house – the person in charge – is gendered male. Yet is this still the case?
‘If we find that audio-technical discourse renders signal processing in terms of masculinist languages of mastery and domination of nature, can we help but wonder after its broader social implications? Does it not also suggest a gendered set of relations to these technologies? It is any wonder we still find the design, implementation, marketing, and use of audio-signal processing technologies to be male-dominated fields? [To change things] it will require fundamentally rethinking how we model, describe, interact, and sound with signal processing technologies’.
For feminist women who felt systematically excluded from certain kinds of cultural and economic activity, the gendering of language was an extension of violence they experienced because they were women.
Making the tape a MISTRESS may help rectify the problem, as does crossing out the very idea of a master copy.
The magnetic viewer makes the mysterious tracks recorded onto the tape visible
We use a Sigma Hi-Chemical MV-95 magnetic viewer in order to aid our digitisation work. By pressing the viewer against the tape we are able to read the magnetic information recorded on it. The reader helps us to visually identify the position of the recorded tracks on the tape, and enables accurate playback during digitisation. Magnetic readers can also help us to identify potential problems with the tape, for example if a track has been partially erased, because it will show up on the viewer.
We receive tapes that are in varying states of repair and disrepair. Sometimes the person who made the recording kept the tapes in impeccable, temperature controlled conditions. Inscribed on the boxes are dates and lists of who performed, and what instrument they played. The tapes often feature detailed notes about the number of tracks recorded, whether they are in stereo or mono and if they used noise reduction technology. Digitisation, in such cases, does not usually pose great challenges.
At the other extreme are tapes recorded by people who never wrote anything down about how they made their recording. This means the people doing the digitising can be left to do a lot of guess work (particularly if that person has since died, and can’t tell you anything about the recording). A lack of informative metadata about the tape does not necessarily create migration difficulties: recordings can be very straightforward like, for example, a ½ track stereo recording of a single voice.
It is essential that the appropriate head is used to read the magnetic information recorded onto the tape.
Problems can however arise when recordings have been made in an idiosyncratic (and inconsistent) manner. For example (and in exceptional circumstances) we receive single magnetic tapes that have a mixture of track formats on them which include four track multi-track, ½ and ¼ track mono and ½ and ¼ track stereo.
In such cases it can be hard to discern the precise nature of the recordings using the ears alone. Often such recordings don’t sound ‘quite right’, even if it is not exactly clear what the problem is.
Rather than relying on speculation, using the magnetic reader gives 100% confirmation about where tracks are recorded on the tape, and therefore helps us to replay the tape using the appropriate playback heads, and therefore digitise it accurately.
If you are new to the world of digital preservation, you may be feeling overwhelmed by the multitude of technical terms and professional practices to contend with, and the fact that standards never seem to stay in place for very long.
Fortunately, there are many resources related to digital preservation available on the internet. Unfortunately, the large amount of websites, hyperlinks and sub-sections can exacerbate those confounded feelings.
In order to help the novice, nerd or perplexed archivist wanting to learn more, we thought it would be useful to compile a selection of (by no means exhaustive) resources to guide your hand. Ultimately if content is to be useful it does need to be curated and organised.
Bear in mind that individual websites within the field tend to be incredibly detailed, so it is worth having a really good explore to find the information you need! And, as is the norm with the internet, one click leads to another so before you know it you stumble upon another interesting site. Please feel free to add anything you find to the comment box below so the list can grow!
Digital Preservation
AV Preserve are a US-based consultation company who work in partnership with organisations to help them implement digital information preservation and dissemination plans. They have an amazing ‘papers and presentation’ section of their website, which includes research about diverse areas such as assessing cloud storage, digital preservation software, metadata, making an institutional case for digital preservation, managing personal archives, primers on moving image codecs, disaster recovery and many more. It is a treasure trove, and there is a regularly updated blog to boot!
The Digital Preservation Coalition‘s website is full of excellent resources including a digital preservation jargon buster, case studies, preservation handbook and a ‘what’s new’ section. The Technology Watch Reports are particularly useful. Of relevance to the work Great Bear do is the ‘Preserving Moving Pictures and Sound’, but there are many others including Intellectual Property and Copyright, Preserving Metadata and Digital Forensics.
Preservation Guide Wiki – Set up initially by Richard Wright, BBC as early as 2006, the wiki provides advice on getting started in audiovisual digital preservation, developing a strategy at institutional and project based levels.
The PrestoCentre’s website is amazing resource to explore if you want to learn more about digital preservation. The organisation aim to ‘enhance the audiovisual sector’s ability to provide long-term access to cultural heritage’. They have a very well stocked library that is composed of tools, case studies and resources, as well as a regularly updated blog.
The European Archival Records and Knowledge Preservation (E-Ark) project promises to collect important research about the sustainability of digital archives across Europe. The website is currently being developed so don’t expect much from it, but it is good to know this research is happening.
The A/V Artifact Atlas is a community-generated resource for people working in digital preservation and aims to identify problems that occur when migrating tape-based media. The Atlas is made in a wiki-format and welcomes contributions from people with expertise in this area – ‘the goal is to collectively build a comprehensive resource that identifies and documents AV artifacts.’ The Atlas was created by people connected to the Bay Area Video Coalition, a media organisation that aims to inspire ‘social change by empowering media makers to develop and share diverse stories through art, education and technology.’
Richard Hess is a US-based audio restoration expert. Although his website looks fairly clunky, he is very knowledgeable and well-respected in the field, and you can find all kinds of esoteric tape wisdom on there.
The National Technology Alliance’s Magnetic Tape Storage and Handling: A Guide for Libraries and Archives by Dr. John W.C. Van Bogart (1995) is an excellent resource, written in non-technical language and explores the kinds of things that can go wrong with magnetic tape (and how to avoid it!)
The National Film and Sound Archive of Australia have produced an in-depth online Preservation Guide. It includes a film preservation handbook, an audiovisual glossary, advice on caring for your collection and disaster management.
The British Library’s Playback and Recording Equipment directory is well worth looking through. Organised chronologically (from 1877 – 1990s), by type and by model, it includes photos, detailed descriptions and you can even view the full metadata for the item. So if you ever wanted to look at a Columbia Gramophone from 1901 or a SONY O-matic tape recorder from 1964, here is your chance!
Digital Heritage
In 2005 UNESCO declared 27 October to be World Audiovisual Heritage Day. The web pages are an insight into the way audiovisual heritage is perceived by large, international policy bodies.
The Digital Curation Centre works to support Higher Education Institutions to interpret and manage research data. Again, this website is incredibly detailed, presenting case studies, ‘how-to’ guides, advice on digital curation standards, policy, curation lifecycle and much more.
Europeana is a multi-lingual online collection of millions of digitized items from European museums, libraries, archives and multi-media collections.
Digital Preservation Tools and Software
For open source digital preservation software check out The Open Planets Foundation (OPF), who address core digital preservation challenges by engaging with its members and the community to develop practical and sustainable tools and services to ensure long-term access to digital content. The website also includes the very interesting Atlas of Digital Damages
Archivematica is a free and open-source digital preservation system that is designed to maintain standards-based, long-term access to collections of digital objects.
The BBC’s R & D Archive is an invaluable resource of white papers, research and policy relating to broadcast technology from the 1930s onwards. As the website states, ‘whether it’s noise-cancelling microphones in the 1930s, the first transatlantic television transmission in the 1950s, Ceefax in the 1970s, digital radio in the 1990s and HD TV in the 2000s, or the challenge to “broadcasting” brought about by the internet and interactive media, BBC Research & Development has led the way with innovative technology and collaborative ways of working.’
As mentioned above, please feel free to add your website or project to the comment box below. We will continue to update this list!
The summer of 2008 saw a spate of articles in the media focusing on a new threat to magnetic tapes.
The reason: the warm, wet weather was reported as a watershed moment in magnetic tape degradation, with climate change responsible for the march of mould consuming archival memories, from personal to institutional collections.
The connection between climate change and tape mould is not one made frequently by commentators, even in the digital preservation world, so what are the links? It is certainly true that increased heat and moisture are prime conditions for the germination of the mould spores that populate the air we breathe. These spores, the British Library tell us
‘can stay dormant for long periods of time, but when the conditions are right they will germinate. The necessary conditions for germination are generally:
• temperatures of 10-35ºC with optima of 20ºC and above
• relative humidities greater than 70%’
The biggest threat to the integrity of magnetic tape is fluctuations in environmental temperatures. This means that tape collections that are not stored in controlled settings, such as a loft, cupboard, shed or basement, are probably most at risk.
While climate change has not always been taking as seriously as it should be by governments and media commentators, the release today of the UN’s report, which stated in no uncertain terms that climate change is ‘severe, pervasive and irreversible’, should be a wake up call to all the disbelievers.
To explore the links between climate change and tape degradation further we asked Peter Specs from US-based disaster recovery specialists the Specs Brothers if he had noticed any increase in the number of mouldy tapes they had received for restoration. In his very generous reply he told us:
‘The volume of mouldy tapes treated seems about the same as before from areas that have not experienced disasters but has significantly increased from disaster areas. The reason for the increase in mould infected tapes from disaster areas seems to be three-fold. First, many areas have recently been experiencing severe weather that is not usual for the area and are not prepared to deal with the consequences. Second, a number of recent disasters have affected large areas and this delays remedial action. Third, after a number of disasters, monies for recovery seem to have been significantly delayed. We do a large amount of disaster recovery work and, when we get the tapes in for processing fairly quickly, are generally able to restore tapes from floods before mould can develop. In recent times, however, we are getting more and more mouldy tapes in because individuals delayed having them treated before mould could develop. Some were unaware that lower levels of their buildings had suffered water damage. In other areas the damage was so severe that the necessities of life totally eclipsed any consideration of trying to recover “non-essential” items such as tape recordings. Finally, in many instances, money for recovery was unavailable and individuals/companies were unwilling to commit to recovery costs without knowing if or when the government or insurance money would arrive.’
Nigel Bewley, soon to be retired senior sound engineer at the British Library, also told us there had been no significant increase in the number of mouldy tapes they had received for treatment. Yet reading between the lines here, and thinking about what Pete Specs told us, in an age of austerity and increased natural disasters, restoring tape collections may slip down the priority list of what needs to be saved for many people and institutions.
Mould: Prevention Trumps the Cure
Climate change aside, what can be done to prevent your tape collections from becoming mouldy? Keeping the tapes stored in a temperature controlled environment is very important – ’15 + 3° C and 40% maximum relative humidity (RH) are safe practical storage conditions,’ recommend the National Technology Alliance. It is also crucial that storage environments retain a stable temperature, because significant changes in the storage climate risk heating or cooling the tape pack, making the tension in the tape pack increase or decrease which is not good for the tape.
Because mould spores settle in very still air, it is vital to ensure a constant flow of air and prevent moist conditions. If all this is too late and your tape collections are already mouldy, all is not lost – even the most infected tape can be treated carefully and salvaged and we can help you do this.
If you are wondering how mould attacks magnetic tape, it is attracted to the binder or adhesive that attaches the layers of the tape together. If you can see the mould on the tape edges it usually means the mould has infected the whole tape.
Optical media can also be affected by mould. Miriam B. Kahn writes in Disaster Response and Planning for Libraries
‘Optical discs are susceptible to water, mould and mildew. If the polycarbonate surface is damaged or not sealed appropriately, moisture can become trapped and begin to corrode the metal encoding surface. If moisture or mould is invasive enough, it will make the disc unreadable’ (85).
Prevention, it seems, is better than having to find the cure. So turn on the lights, keep the air flowing and make the RH level stable.
The history of amateur recording is peppered with examples of people who stretched technologies to their creative limit. Whether this comes in the form of hours spent trying things out and learning through doing, endlessly bouncing tracks in order to turn an 8-track recording into a 24-track epic or making high quality audio masters on video tape, people have found ways to adapt and experiment using the tools available to them.
One of the lesser known histories of amateur home recordings is making high quality stereo mixdowns and master recordings from multi-track audio tape onto consumer-level Hi-Fi VCRs.
We are currently migrating a stereo master VHS Hi-Fi recording of London-based indie band Hollow Hand. Hollow Hand later adopted the name Slanted and were active in London between 1992-1995. The tapes were sent in by Mark Venn, the bass player with Slanted and engineer for these early recordings that were recorded in 1992 in the basement of a Clapham squat. Along with the Hi-Fi VHS masters, we have also been sent eight reels of AMPEX ¼ tapes of Slanted that are being transferred for archival purposes. Mark intends to remix the eight track recordings digitally but as of yet has no plans for a re-release.
When Mark sent us the tapes to be digitised he thought they had been encoded with a SONY PCM, a mixed digital/ analogue recording method we have covered in a previous blog post. The tapes had, however, been recorded directly from the FOSTEX eight track recorder to the stereo Hi-Fi function on a VHS video tape machine. For Mark at the time this was the best way to get a high quality studio master because other analogue and digital tape options, such as Studer open reel to reel and DAT machines, were financially off-limits to him. It is worth mentioning that Hi-Fi audio technologies were introduced in the VHS model by JVC around 1984, so using this method to record stereo masters would have been fairly rare, even among people who did a lot of home recording. It was certainly a bit of a novelty in the Great Bear Studio – they are the first tapes we have ever received that have been recorded in this way – and take it for granted that we see a lot of tape.
Using the Hi-Fi function on VHS tape machines was probably as good as it got in terms of audio fidelity for those working in an exclusively analogue context. It produced a master recording comparable in quality to a CD, particularly if the machine had manual audio recording level control. This is because, as we wrote about in relation to PCM/ Betamax, video tape could accommodate greater bandwidth that audio tape (particularly audio cassette), therefore leading to better quality recordings.
One of our replacement upper head drums
VHS Hi-Fi audio is achieved using audio frequency-modulation (AFM) and relied on a form of magnetic recording called ‘depth multiplexing‘. This is when
‘the modulated audio carrier pair was placed in the hitherto-unused frequency range between the luminance and the colour carrier (below 1.6 MHz), and recorded first. Subsequently, the video head erases and re-records the video signal (combined luminance and colour signal) over the same tape surface, but the video signal’s higher centre frequency results in a shallower magnetization of the tape, allowing both the video and residual AFM audio signal to coexist on tape.’
Challenges for migrating Hi-Fi VHS Audio
Although the recordings of Hollow Hand are in good working condition, analogue masters to VHS Hi-Fi audio do face particular challenges in the migration process.
Playing back the tapes in principle is easy if both tape and machine are in optimum condition, but if either are damaged the original recordings can be hard to reproduce.
A particular problem for Hi-Fi audio emerges when the tape heads wear and it becomes harder to track the hi-fi audio recording because the radio frequency signal (RF) can’t be read consistently off the tape. Hi-Fi recordings are harder to track because of depth multiplexing, namely the position of the recorded audio relative to the video signal. Even though there is no video signal as such in the playback of Hi-Fi audio, the video signal is still there, layered on top of the audio signal, essentially making it harder to access. Of course when tape heads/ drums wear down they can always be replaced, but acquiring spare parts will become increasingly difficult in years to come, making Hi-Fi audio recordings on VHS particularly threatened.
In order to migrate tape-based media to digital files in the most effective way possible, it is important to use appropriate machines for the transfer. The Panasonic AG-7650 we used to transfer the Hollow Hand tapes afforded us great flexibility because it is possible to select which audio tracks are played back at any given time which meant we could isolate the Hi-Fi audio track. The Panasonic AG-7650 also has tracking meters which makes it easy to assess and adjust the tracking of the tape and tape head where necessary.
As ever, the world of digitisation continues to generate anomalies, surprises and good stories. Who knows how many other video/ audio hybrid tapes are out there! If you do possess an archive collection of such tapes we advise you to take action to ensure they are migrated because of the unique problems they pose as a storage medium.
Whole subcultures have emerged in this memory boom, as digital technologies enable people to come together via a shared passion for saving obscurities presumed to be lost forever. One such organisation is Kaleidoscope, whose aim is to keep the memory of ‘vintage’ British television alive. Their activities capture an urgent desire bubbling underneath the surface of culture to save everything, even if the quality of that everything is questionable.
Of course, as the saying goes, one person’s rubbish is another person’s treasure. As with most cultural heritage practices, the question of value is at the centre of people’s motivations, even if that value is expressed through a love for Pan’s People, Upstairs, Downstairs, Dick Emery and the Black and White Minstrel Show.
We were recently contacted by a customer hunting for lost TV episodes. His request: to lay hands on any old tapes that may unwittingly be laden with lost jewels of TV history. His enquiry is not so strange since a 70s Top of the Pops programme, a large proportion of which were deleted from the official BBC archive, trailed the end of ½ EIAJ video tape we recently migrated. And how many other video tapes stored in attics, sheds or barns potentially contain similar material? Or, as stated on the Kaleidoscope website:
‘Who’d have ever imagined that a modest, sometimes mould-infested collection of VHS tapes in a cramped back bedroom in Pill would lead to the current Kaleidoscope archive, which hosts the collections of many industry bodies as well as such legendary figures as Bob Monkhouse or Frankie Howard?’
Selection and appraisal in the archive
Mysterious tapes?
Living in an age of seemingly infinite information, it is easy to forget that any archival project involves keeping some things and throwing away others. Careful considerations about the value of an item needs to be made, both in relation to contemporary culture and the projected needs of subsequent generations.
These decisions are not easy and carry great responsibility. After all, how is it possible to know what society will want to remember in 10, 20 or even 30 years from now, let alone 200? The need to remember is not static either, and may change radically over time. What is kept now also strongly shapes future societies because our identities, lives and knowledge are woven from the memory resources we have access to. Who then would be an archivist?
When faced with a such a conundrum the impulse to save everything is fairly seductive, but this is simply not possible. Perhaps things were easier in the analogue era when physical storage constraints conditioned the arrangement of the archive. Things had to be thrown away because the clutter was overwhelming. With the digital archive, always storing more seems possible because data appears to take up less space. Yet as we have written about before on the blog, just because you can’t touch or even see digital information, doesn’t mean it is not there. Energy consumption is costly in a different way, and still needs to be accounted for when appraising how resource intensive digital archives are.
For those who want their media memories to remain intact, whole and accessible, learning about the clinical nature of archival decisions may raise concern. The line does however need to be drawn somewhere. In an interview in 2004 posted on the Digital Curation Centre’s website, Richard Wright, who worked in the BBC’s Information and Archives section, explained the long term preservation strategy for the institution at the time.
‘For the BBC, national programmes that have entered the main archive and been fully catalogued have not, in general, been deleted. The deletions within the retention policy mainly apply to “contribution material” i.e. components (rushes) of a final programme, or untransmitted material. Hence, “long-term” for “national programmes that have entered the main archive and been fully catalogued” means in perpetuity. We have already kept some material for more than 75 years, including multiple format migrations.’
Value – whose responsibility?
For all those episodes, missing believed wiped, the treasure hunters who track them down tread a fine line between a personal obsession and offering an invaluable service to society. You decide.
What is inspiring about amateur preservationists is that they take the question of archival value into their own hands. In the 21st century, appraising and selecting the value of cultural artifacts is therefore no longer the exclusive domain of the archivist, even if expertise about how to manage, describe and preserve collections certainly is.
Does the popularity of such activities change the constitution of archives? Are they now more egalitarian spaces that different kinds of people contribute to? It certainly suggests that now, more than ever, archives always need to be thought of in plural terms, as do the different elaborations of value they represent.
We are pleased to announce that we are now able to support the transfer of 2″ Quadruplex Video Tape (PAL, SECAM & NTSC) to digital formats.
2” Quad was a popular broadcast analogue video tape format whose halcyon period ran from the late 1950s to the 1970s. The first quad video tape recorder made by AMPEX in 1956 cost a modest $45,000 (that’s $386,993.38 in today’s money).
2” Quad revolutionized TV broadcasting which previously had been reliant on film-based formats, known in the industry as ‘kinescope‘ recordings. Kinescope film required significant amounts of skilled labour as well as time to develop, and within the USA, which has six different time zones, it was difficult to transport the film in a timely fashion to ensure broadcasts were aired on schedule.
To counter these problems, broadcasters sought to develop magnetic recording methods, that had proved so successful for audio, for use in the television industry.
The first experiments directly adapted the longitudinal recording method used to record analogue audio. This however was not successful because video recordings require more bandwidth than audio. Recording a video signal with stationary tape heads (as they are in the longitudinal method), meant that the tape had to be recorded at a very high speed in order accommodate sufficient bandwidth to reproduce a good quality video image. A lot of tape was used!
Ampex, who at the time owned the trademark marketing name for ‘videotape’, then developed a method where the tape heads moved quickly across the tape, rather than the other way round. On the 2” quad machine, four magnetic record/reproduce heads are mounted on a headwheel spinning transversely (width-wise) across the tape, striking the tape at a 90° angle. The recording method was not without problems because, the Toshiba Science Museum write, it ‘combined the signal segments from these four heads into a single video image’ which meant that ‘some colour distortion arose from the characteristics of the individual heads, and joints were visible between signal segments.’
The limitations of Quadruplex recording influenced the development of the helical scan method, that was invented in Japan by Dr. Kenichi Sawazaki of the Mazda Research Laboratory, Toshiba, in 1954. Helical scanning records each segment of the signal as a diagonal stripe across the tape. ‘By forming a single diagonal, long track on two-inch-wide tape, it was possible to record a video signal on one tape using one head, with no joints’, resulting in a smoother signal. Helical scanning was later widely adopted as a recording method in broadcast and domestic markets due to its simplicity, flexibility, reliability and economical use of tape.
This brief history charting the development of 2″ Quad recording technologies reveals that efficiency and cost-effectiveness, alongside media quality, were key factors driving the innovation of video tape recording in the 1950s.
What is particularly interesting about the consortium E-Ark has brought together is commercial partners will be part of a conversation that aims to establish long term solutions for digital preservation across Europe. More often than not, commercial interests have driven technological innovations used within digital preservation. This has made digital data difficult to manage for institutions both large and small, as the BBC’s Digital Media Initiative demonstrates, because the tools and protocols are always in flux. A lack of policy-level standards and established best practices has meant that the norm within digital information management has very much been permanent change.
Such a situation poses great risks for both digitised and born digital collections because information may have to be regularly migrated in order to remain accessible and ‘open’. As stated on the E-Ark website, ‘the practices developed within the project will reduce the risk of information loss due to unsuitable approaches to keeping and archiving of records. The project will be public facing, providing a fully operational archival service, and access to information for its users.’
The E-Ark project will hopefully contribute to the creation of compatible systems that can respond to the different needs of groups working with digital information. Which is, of course, just about everybody right now: as the world economy becomes increasingly defined by information and ‘big data’, efficient and interoperable access to commercial and non-commercial archives will be an essential part of a vibrant and well functioning economic system. The need to establish data systems that can communicate and co-operate across software borders, as well as geographical ones, will become an economic necessity in years to come.
The task facing E-Ark is huge, but one crucial to implement if digital data is to survive and thrive in this brave new datalogical world of ours. As E-Ark explain: ‘Harmonisation of currently fragmented archival approaches is required to provide the economies of scale necessary for general adoption of end-to-end solutions. There is a critical need for an overarching methodology addressing business and operational issues, and technical solutions for ingest, preservation and re-use.’
Maybe 2014 will be the year when digital preservation standards start to become a reality. As we have already discussed on this blog, the US-based National Agenda for Digital Stewardship 2014 outlined the negative impact of continuous technological change and the need to create dialogue among technology makers and standards agencies. It looks like things are changing and much needed conversations are soon to take place, and we will of course reflect on developments on the Great Bear blog.
Philip Jap came from a time when mime, dance, slapped bass lines, mascara and techno-dystopic anthems were staple parts of a successful popular music career. Cut from the same new wave goth cloth as Gary Numan, Human League and John Foxx, sporting mesmeric dance moves like a male Kate Bush, Jap lit up the early 1980s with performances on the David Essex Showcase, an audience participation talent show similar to today’s Britain’s Got Talent or Pop Idol. Jap went on to sign for Carlin Music Publishing and A&M Records, release an eponymous solo album and have a top 40 hit with ‘Save Us,’ a dramatic plea for liberation from an increasingly intrusive ‘mechanical world.’
Jap retains a modest yet loyal fanbase (The Philip Jap Army), and his recordings will soon be made available through his twitter site. Although he did not have runaway commercial chart success, Jap went on to have a successful career as a composer and arranger for TV series and commercials and is the co-founder of AUDIOfield, a music production company.
The Greatbear studio has been graced with Jap’s music this week because we have been migrating a collection of low-band U-matic videos that feature a number of TV appearances and promotional videos, including the 30 minute ‘special’ that was recorded for the BBC. In similar fashion to our recent transfer of Manchester Oi! band State Victims, the tapes were found in an old suitcase in a barn!
Although the tapes were mostly in good condition, some of the tapes were recorded on early SONY brand and were suffering from low Radio Frequency (RF) levels. RF levels are the recorded levels that can be read off the tape itself. To get a good, clear picture it is essential that the RF levels are strong. According to the AV Artifact Atlas, RF deterioration can occur because of a ‘poorly made recording on broken or mis-calibrated machine/record heads, or the use of poor quality video tape stock.’ Low RF levels may also occur if ‘the source media itself has been exposed to a strong magnetic field (unshielded speakers, motors, high-voltage transformers, etc.)’.
When a tape is suffering from low RF levels there are not loads of things you can do to reverse the process. This is because the signal recorded on the tape has essentially faded over time, due to a bad initial recording, unsuitable storage conditions leading to de-magnetisation or sticky shed, or poor quality tape (such as AMPEX or SONY U-matic tapes, although not exclusively). It is possible however to modify the tracking, a calibration adjustment which ensures the spinning playback head is properly aligned with the helical scan signal written onto the video tape. Tracking changes the speed at which the tape moves past the tape heads, which although spinning during playback, remain stationary. It is not the answer of all low RF ills, however, because the signal on the tape itself has become weaker, even if the calibration adjustment helps the machine read the signal more effectively.
Thankfully the tapes play back well, which is pretty amazing given that the tapes are over 30 years old and were never meant to be archive copies in the first place. We have also had a pretty enjoyable time watching and listening to Philip Jap’s amazing music. It is definitely time for a revival!
We understand that when organisations decide to digitise magnetic tape collections the whole process can take significant amounts of time. From initial condition appraisals, to selecting which items to digitise, many questions, as well as technical and cultural factors, have to be taken into account before a digital transfer can take place.
This is further complicated by that fact that money is not readily available for larger digitisation projects and specific funding has to be sought. Often an evidence base has to be collected to present to potential funders about the value and importance of a collection, and this involves working with organisations who have specific expertise in transferring tape-based collections to digital formats to gain vital advice and support.
We are very happy to work with organisations and institutions during this crucial period of collection assessment and bid development. We understand that even during the pre-application stage informed decisions need to be made about the conditions of tape, and realistic anticipations of what treatments may be required during a particular digitisation project. We are very willing to offer the support and advice that will hopefully contribute to the development of a successful bid.
For example, we recently were contacted by Ken Turner who was involved in Action Space, an experimental, community theatre group established in 1968. Ken has a collection of nearly 40 EIAJ SONY video tapes that were made in the 1980s. Because of the nature of the tapes, which almost always require treatment before they can be played back, transferring the whole collection will be fairly expensive so funding will be necessary to make the project happen. We have offered to do a free assessment of the tapes and provide a ten minute sample of the transfer that can be used as part of an evidence base for a funding bid.
Potential Problems with EIAJ ½ Video Tapes
The EIAJ video tape recorder was developed in the late 1960s and is a fairly important format in the history of recordable media. As the first standardized video tape machine, it could playback tapes made by different companies and therefore made video use far cheaper and more widespread, particularly within a domestic context. The EIAJ standard had a similar democratising impact on non-professional video recording due to its portability, low cost, and versatility.As mentioned above, the EIAJ tapes almost always require treatment before they can be played back, particularly the SONY V30-H and V60-H tapes. Problems with the tape are indicated by squealing and shedding upon playback. This is an example of what the AV Artifact Atlas describe as stiction, ‘when media suffering from hydrolysis or contamination is restricted from moving through the tape path correctly.’ When stiction occurs the tape needs to be removed from the transport and treated immediately, either through baking and cleaning, before the transfer can be completed.
EIAJ tapes that have a polyethylene terephthalate ‘back coating’ or ‘substrate’ may also be affected by temperature or humidity changes in its storage environment. These may have caused the tape pack to expand or contract, therefore resulting in permanent distortion of the tape backing. Such problems are exacerbated by the helical scan method of recording which is common to video tape, which records parallel tracks that run diagonally across the tape from one edge to the other. If the angle that the recorded tracks make to the edge of the tape do not correspond with the scan angle of the head (which always remains fixed), mistracking and information loss can occur, which can lead to tracking errors. Correcting tracking errors is fairly easy as most machines have in-built tracking controls. Some of the earliest SONY CV ½ inch video tape machines didn’t have this function however, so this presents serious problems for the migration of these tapes if their back coating has suffered deformation.
The possibility of collaboration
We are excited about the possibility of working with the Action Space collection, mainly because we would love to opportunity to learn more about their work. Like many other theatre groups who were established in the late 1960s, Action Space wanted to challenge the elitism of art and make it accessible to everyone in the community. In their 1972 annual report, which is archived on the Unfinished Histories: Recording the History of Alternative Theatre website, they describe the purposes of the company as follows:
‘Its workings are necessarily experimental, devious, ambiguous, and always changing in order to find a new situation. In the short term the objectives are to continually question and demonstrate through the actions of all kinds new relationships between artists and public, teachers and taught, drop-outs and society, performers and audiences, and to question current attitudes of the possibility of creativity for everyone. For the longer term the aim is to place the artists in a non-elite set up, to keep “normal” under revision, to break barriers in communication and to recognise that education is a continuing process.’
Although Action Space disbanded in 1981, the project was relaunched in the same year as Action Space Mobile, who are still operating today. The centre of the Action Space Mobile’s philosophy is that they are an arts company ‘that has always worked with people, believing that contact and participation in the arts can change lives positively.’ There is also the London based ActionSpace, who work with artists with learning disabilities.
We hope that offering community heritage projects the possibility of collaboration will help them to benefit from our knowledge and experience. In turn we will have interesting things to watch and listen to, which is part of what makes working in the digitisation world fun and enjoyable.
In a technological world that is rapidly changing how can digital information remain accessible?
One answer to this question lies in the use of open source technologies. As a digital preservation strategy it makes little sense to use codecs owned by Mac or Windows to save data in the long term. Propriety software essentially operate like closed systems and risk compromising access to data in years to come.
It is vital, therefore, that the digitisation work we do at Great Bear is done within the wider context of digital preservation. This means making informed decisions about the hardware and software we use to migrate your tape-based media into digital formats. We use a mixture of propriety and open source software, simply because it makes our a bit life easier. Customers also ask us to deliver their files in propriety formats. For example, Apple pro res is a really popular codec that doesn’t take up a lot of data space so our customers often request this, and of course we are happy to provide it.
Using open systems definitely has benefits. The flexibility of Linux, for example, enables us to customise our digitisation system according to what we need to do. As with the rest of our work, we are keen to find ways to keep using old technologies if they work well, rather than simply throwing things away when shiny new devices come on the market. There is the misconception that to ingest vast amounts of audio data you need the latest hardware. All you need in fact is a big hard drive, flexible, yet reliable, software and an operating system that doesn’t crash so it can be left to ingest for 8 hours or more. Simple! Examples of open source software we use is the sound processing programme SoX. This saves us a lot of time because we are able to write scripts for the programme that can be used to batch process audio data according to project specifications.
Openness in the digital preservation world
Within the wider digital preservation world open source technologies are also used widely. From digital preservation tools developed by projects such as SCAPE and the Open Planets Foundation, there are plenty of software resources available for individuals and organisations who need to manage their digital assets. It would be naïve, however, to assume that the practice of openness here, and in other realms of the information economy, are born from the same techno-utopian impulse that propelled the open software movement from the 1970s onwards. The SCAPE website makes it clear that the development of open source information preservation tools are ‘the best approach given the substantial public investment made at the European and national levels, and because it is the most effective way to encourage commercial growth.’
What would make projects like SCAPE and Open Planets even better is if they thought about ways to engage non-specialist users who may be curious about digital preservation tools but have little experience of navigating complex software. The tools may well be open, but the knowledge of how to use them are not.
‘The problem is most archivists, curators and conservators involved in media reformatting are ill-equipped to detect artifacts, or further still to understand their cause and ensure a high quality job. They typically don’t have deep training or practical experience working with legacy media. After all, why should we? This knowledge is by and large the expertise of video and audio engineers and is increasingly rare as the analogue generation ages, retires and passes on. Over the years, engineers sometimes have used different words or imprecise language to describe the same thing, making the technical terminology even more intimidating or inaccessible to the uninitiated. We need a way capture and codify this information into something broadly useful. Preserving archival audiovisual media is a major challenge facing libraries, archives and museums today and it will challenge us for some time. We need all the legs up we can get.’
The promise of openness can be a fraught terrain. In some respects we are caught between a hyper-networked reality, where ideas, information and tools are shared openly at a lightning pace. There is the expectation that we can have whatever we want, when we want it, which is usually now. On the other side of openness are questions of ownership and regulation – who controls information, and to what ends?
Perhaps the emphasis placed on the value of information within this context will ultimately benefit digital archives, because there will be significant investment, as there already has been, in the development of open resources that will help to take care of digital information in the long term.
‘A non-magnetic, 100 year, green solution for data storage.’
This is the stuff of digital information managers’ dreams. No more worrying about active data management, file obsolescence or that escalating energy bill.
Imagine how simple life would be if there was a way to store digital information that could last, without intervention, for nearly 100 years. Those precious digital archives could be stored in a warehouse that was not climate controlled, because the storage medium was resilient enough to withstand irregular temperatures.
Imagine after 100 years an archivist enters that very same warehouse to retrieve information requested by a researcher. The archivist pulls a box off the shelf and places it on the table. In their bag they have a powerful magnifying glass which they use to read the information. Having ascertained they have the correct item, they walk out the warehouse, taking the box with them. Later that day, instructions provided as part of the product licensing over 100 years ago are used to construct a reader that will retrieve the data. The information is recovered and, having assessed the condition of the storage medium which seems in pretty good nick, the digital optical technology storage is taken back to the warehouse where it sits for another 10 years, until it is subject to its life-cycle review.
Does this all sound too good to be true? For anyone exposed to the constantly changing world of digital preservation, the answer would almost definitely be yes. We have already covered on this blog numerous issues that the contemporary digital information manager may face. The lack of standardisation in technical practices and the bewildering array of theories about how to manage digital data mean there is currently no ‘one size fits all’ solution to tame the archive of born-digital and digitised content, which is estimated to swell to 3,000 Exabytes (thousands of petabytes) by 2020*. We have also covered the growing concerns about the ecological impact of digital technologies, such as e-waste and energy over-consumption. With this in mind, the news that a current technology exists that can by-pass many of these problems will seem like manna from heaven. What can this technology be and why have you never heard about it?
The technology in question is called DOTS, which stands for Digital Optical Technology System. The technology is owned and being developed by Group 47, who ‘formed in 2008 in order to secure the patents, designs, and manufacturing processes for DOTS, a proven 100-year archival technology developed by the Eastman Kodak Company.’ DOTS is refreshingly different from every other data storage solution on the market because it ‘eliminates media and energy waste from forced migration, costly power requirements, and rigid environmental control demands’. What’s more, DOTS are ‘designed to be “plug & play compatible” with the existing Linear Tape Open (LTO) tape-based archiving systems & workflow’.
In comparison with other digital information management systems that can employ complex software, the data imaged by DOTS does not use sophisticated technology. John Lafferty writes that at ‘the heart of DOTS technology is an extremely stable storage medium – metal alloy sputtered onto mylar tape – that undergoes a change in reflectivity when hit by a laser. The change is irreversible and doesn’t alter over time, making it a very simple yet reliable technology.’
DOTS can survive the benign neglect all data experiences over time, but can also withstand pretty extreme neglect. During research and development, for example, DOTS was exposed to a series of accelerated environmental age testing that concluded ‘there was no discernible damage to the media after the equivalent of 95.7 years.’ But the testing did not stop there. Since acquiring patents for the technology Group 47,
‘has subjected samples of DOTS media to over 72 hours of immersion each in water, benzine, isopropyl alcohol, and Clorox (™) Toilet Bowl Cleaner. In each case, there was no detectable damage to the DOTS media. However, when subjected to the citric acid of Sprite carbonated beverage, the metal had visibly deteriorated within six hours.’
Robust indeed! DOTS is also non-magnetic, chemically inert, immune from electromagnetic fields and can be stored in normal office environments or extremes ranging from -9º – 65º C. It ticks all the boxes really.
DOTS vs the (digital preservation) world
The only discernible benefit of the ‘open all hours’, random access digital information culture over a storage solution such as DOTS is accessibility. While it certainly is amazing how quick and easy it is to retrieve valuable data at the click of a button, it perhaps should not be the priority when we are planning how to best take care of the information we create, and are custodians of. The key words here are valuable data. Emerging norms in digital preservation, which emphasise the need to always be responsive to technological change, takes gambles with the very digital information it seeks to preserve because there is always a risk that migration will compromise the integrity of data.
The constant management of digital data is also costly, disruptive and time-consuming. In the realm of cultural heritage, where organisations are inevitably under resourced, making sure your digital archives are working and accessible can sap energy and morale. These issues of course affect commercial organisations too. The truth is the world is facing an information epidemic, and surely we would all rest easier if we knew our archives were safe and secure. Indeed, it seems counter-intuitive that amid the endless flashy devices and research expertise in the world today, we are yet to establish sustainable archival solutions for digital data.
Of course, using a technology like DOTS need not mean we abandon the culture of access enabled by file-based digital technologies. It may however mean that the digital collections available on instant recall are more carefully curated. Ultimately we have to ask if privileging the instant access of information is preferable to long-term considerations that will safeguard cultural heritage and our planetary resources.
If such a consideration errs on the side of moderation and care, technology’s role in shaping that hazy zone of expectancy known as ‘the future’ needs to shift from the ‘bigger, faster, quicker, newer’ model, to a more cautious appreciation of the long-term. Such an outlook is built-in to the DOTS technology, demonstrating that to be ‘future proof’ a technology need not only withstand environmental challenges, such as flooding or extreme temperature change, but must also be ‘innovation proof’ by being immune to the development of new technologies. As John Lafferty writes, the license bought with the product ‘would also mandate full backward compatibility to Generation Zero, achievable since readers capable of reading greater data densities should have no trouble reading lower density information.’ DOTS also do not use propriety codecs, as Chris Castaneda reports, ‘the company’s plan is to license the DOTS technology to manufacturers, who would develop and sell it as a non-proprietary system.’ Nor do they require specialist machines to be read. With breathtaking simplicity, ‘data can be recovered with a light and a lens.’
It would be wrong to assume that Group 47’s development of DOTS is not driven by commercial interests – it clearly is. DOTS do however seem to solve many of the real problems that currently afflict the responsible and long-term management of digital information. It will be interesting to see if the technology is adopted and by who. Watch this space!
* According to a 2011 Enterprise Strategy Group Archive TCO Study
2014 will no doubt present a year of new challenges for those involved in digital preservation. A key issue remains the sustainability of digitisation practices within a world yet to establish firm standards and guidelines. Creating lasting procedures capable of working across varied and international institutions would bring some much needed stability to a profession often characterized by permanent change and innovation.
In 1969 The EIAJ-1 video tape was developed by the Electronic Industries Association of Japan. It was the first standardized format for industrial/non-broadcast video tape recording. Once implemented it enabled video tapes to be played on machines made by different manufacturers and it helped to make video use cheaper and more widespread, particularly within a domestic context.
The introduction of standards in the digitisation world would of course have very little impact on the widespread use of digital technologies which are, in the west, largely ubiquitous. It would however make the business of digital preservation economically more efficient, simply because organisations would not be constantly adapting to change. For example, think of the costs involved in keeping up with rapid waves of technological transformation: updating equipment, migrating data and ensuring file integrity and operability are maintained are a few costly and time consuming examples of what this would entail.
Although increasingly sophisticated digital forensic technology can help to manage some of these processes, highly trained (real life!) people will still be needed to oversee any large-scale preservation project. Within such a context resource allocation will always have to account for these processes of adaptation. It has to be asked then: could this money, time and energy be practically harnessed in other, more efficient ways? The costs of non-standardisation becomes ever more pressing when we consider the amount of the digital data preserved by large institutions such as the British Library, whose digital collection is estimated to amass up to 5 petabytes (5000 terabytes) by 2020. This is not a simple case of updating your iphone to the next model, but an extremely complex and risky venture where the stakes are high. Do we really want to jeopardise rich forms cultural heritage in the name of technological progress?
The US-based National Digital Stewardship Alliance (NDSA) National Agenda for Digital Stewardship 2014 echoes such a sentiment. They argue that ‘the need for integration, interoperability, portability, and related standards and protocols stands out as a theme across all of these areas of infrastructure development’ (3). The executive summary also stresses the negative impact rapid technological change can create, and the need to ‘coordinate to develop comprehensive coverage on critical standards bodies, and promote systematic community monitoring of technology changes relevant to digital preservation.’ (2)
File Format Action Plans
One step on the way to more secure standards is the establishment of File Format Action Plans, a practice which is being increasingly recommended by US institutions. The idea behind developing a file format action plan is to create a directory of file types that are in regular use by people in their day to day lives and by institutions. Getting it all down on paper can help us track what may be described as the implicit user-standards of digital culture. This is the basic idea behind Parsimonious Preservation, discussed on the blog last year: that through observing trends in file use we may come to the conclusion that the best preservation policy is to leave data well alone since in practice files don’t seem to change that much, rather than risk the integrity of information via constant intervention.
What are the other main challenges facing ‘digital stewards’ in 2014? In a world of exponential information growth, making decisions about what we keep and what we don’t becomes ever more pressing. When whole collections cannot be preserved digital curators are increasingly called upon to select material deemed representative and relevant. How is it possible to know now what material needs to be preserve for posterity? What values inform our decision making?
To take an example from our work at Great Bear: we often receive tapes from artists who have achieved little or no commercial success in their life times, but whose work is often of great quality and can tell us volumes about a particular community or musical style. How does such work stand up against commercially successful recordings? Which one is more valuable? The music that millions of people bought and enjoyed or the music that no one has ever heard?
Ultimately these questions will come to occupy a central concern for digital stewards of audio data, particularly with the explosion of born-digital music cultures which have enabled communities of informal and often non-commercial music makers to proliferate. How is it possible to know in advance what material will be valuable for people 20, 50 or 100 years from now? These are very difficult, if not impossible questions for large institutions to grapple with, and take responsibility for. Which is why, as members of a digital information management society, it is necessary to empower ourselves with relevant information so we can make considered decisions about our own personal archives.
A final point to stress is that among the ‘areas of concern’ for digital preservation cited by the NDSA, moving image and recorded sound figure highly, alongside other born-digital content such as electronic records, web and social media. Magnetic tape collections remain high risk and it is highly recommended that you migrate this content to a digital format as soon as possible. While digitisation certainly creates many problems as detailed above, magnetic tape is also threatened by physical deterioration and its own obsolescence challenges, in particular finding working machines to play back tape on. The simple truth is, if you want to access material in your tape collections it needs now to be stored in a resilient digital format. We can help, and offer other advice relating to digital information management, so don’t hesitate to get in touch.
What a year it has been in the life of Greatbear Analogue and Digital Media. As always the material customers have sent us to digitise has been fascinating and diverse, both in terms of the recordings themselves and the technical challenges presented in the transfer process. At the end of a busy year we want to take this opportunity to thank our customers for sending us their valuable tape collections, which over the course of 2013 has amounted to a whopping 900 hours of digitised material.
We feel very honoured to play a part in preserving personal and institutional archives that are often incredibly rare, unique and, more often than not, very entertaining. It is a fairly regular occurrence in the Great Bear Studio to have radio jingles from the 60s, oral histories of war veterans, recordings of family get-togethers and video documentation of avant-garde 1970s art experiments simultaneously migrating in a vibrant melee of digitisation.
We have also received a large amount of rare or ‘lost’ audio recordings through which we have encountered unique moments in popular music history. These include live recordings from the Couriers Folk Club in Leicester, demo tapes from artists who achieved niche success like 80s John Peel favourites BOB, and large archives of prolific but unknown songwriters such as the late Jack Hollingshead, who was briefly signed to the Beatles’ Apple label in the 1960s. We always have a steady stream of tapes from Bristol Archive Records, who continue to acquire rare recordings from bands active in the UK’s reggae and post-punk scenes. We have also migrated VHS footage of local band Meet Your Feet from the early 1990s.
On our blog we have delved into the wonderful world of digital preservation and information management, discussing issues such as ‘parsimonious preservation‘ which is advocated by the National Archives, as well as processes such as migration, normalisation and emulation. Our research suggests that there is still no ‘one-size-fits-all’ strategy in place for digital information management, and we will continue to monitor the debates and emerging practices in this field in the coming year. Migrating analogue and digital tapes to digital files remains strongly recommended for access and preservation reasons, with some experts bookmarking 15 April 2023 as the date when obsolescence for many formats will come into full effect.
We have been developing the blog into a source of information and advice for our customers, particularly relating to issues such as copyright and compression/ digital format delivery. We hope you have found it useful!
While the world is facing a growing electronic waste crisis, Great Bear is doing its bit to buck the trend by recycling old domestic and professional tape machines. In 2013 we have acquired over 20 ‘new’ old analogue and digital video machines. This has included early ’70s video cassette domestic machines such as the N1502, up to the most recent obsolete formats such as Digital Betacam. We are always looking for old machines, both working and not working, so do get in touch if your spring clean involves ridding yourself of obsolete tape machines!
Our collection of test equipment is also growing as we acquire more wave form monitors, rare time-based correctors and vectorscopes. In audio preservation we’ve invested heavily in early digital audio machines such as multi-track DTRS and ADAT machines which are rapidly becoming obsolete.
We are very much looking forward to new challenges in 2014 as we help more people migrate their tape-based collections to digital formats. We are particularly keen to develop our work with larger archives and memory institutions, and can offer consultation on technical issues that arise from planning and delivering a large-scale digitisation project, so please do get in touch if you want to benefit from our knowledge and experience.
Once again a big thank you from us at Greatbear, and we hope to hear from you in the new year.
What is the most effective way to store and manage digital data in the long term? This is a question we have given considerable attention to on this blog. We have covered issues such as analogue obsolescence, digital sustainability and digital preservation policies. It seems that as a question it remains unanswered and up for serious debate.
We were inspired to write about this issue once again after reading an article that was published in the New Scientist a year ago called ‘Cassette tapes are the future of big data storage.’ The title is a little misleading, because the tape it refers to is not the domestic audio tape that has recently acquired much counter cultural kudos, but rather archival tape cartridges that can store up to 100 TB of data. How much?! I hear you cry! And why tape given the ubiquity of digital technology these days? Aren’t we all supposed to be ‘going tapeless’?
The reason for such an invention, the New Scientist reveals, is the ‘Square Kilometre Array (SKA), the world’s largest radio telescope, whose thousands of antennas will be strewn across the southern hemisphere. Once it’s up and running in 2024, the SKA is expected to pump out 1 petabyte (1 million gigabytes) of compressed data per day.’
Image of the SKA dishes
Researchers at Fuji and IBM have already designed a tape that can store up to 35TB, and it is hoped that a 100TB tape will be developed to cope with the astronomical ‘annual archive growth [that] would swamp an experiment that is expected to last decades’. The 100TB cartridges will be made ‘by shrinking the width of the recording tracks and using more accurate systems for positioning the read-write heads used to access them.’
If successful, this would certainly be an advanced achievement in material science and electronics. Smaller tape width means less room for error on the read-write function – this will have to be incredibly precise on a tape that will be storing a pretty extreme amount of information. Presumably smaller tape width will also mean there will be no space for guard bands either. Guard bands are unrecorded areas between the stripes of recorded information that are designed to prevent information interference, or what is known as ‘cross-talk‘.They were used on larger domestic video tapes such as U-Matic and VHS, but were dispensed with on smaller formats such as the Hi-8, which had a higher density of magnetic information in a small space, and used video heads with tilted gaps instead of guard bands.
The existence of SKA still doesn’t explain the pressing question: why develop new archival tape storage solutions and not hard drive storage?
Hard drives were embraced quickly because they take up less physical storage space than tape. Gone are the dusty rooms bursting with reel upon reel of bulky tape; hello stacks of infinite quick-fire data, whirring and purring all day and night. Yet when we consider the amount of energy hard drive storage requires to remain operable, the costs – both economic and ecological – dramatically increase.
The report compiled by the Clipper Group published in 2010 overwhelmingly argues for the benefits of tape over disk for the long term archiving of data. They state that ‘disk is more than fifteen times more expensive than tape, based upon vendor-supplied list pricing, and uses 238 times more energy (costing more than the all costs for tape) for an archiving application of large binary files with a 45% annual growth rate, all over a 12-year period.’
This is probably quite staggering to read, given the amount of investment in establishing institutional architecture for tape-less digital preservation. Such an analysis of energy consumption does assume, however, that hard drives are turned on all the time, when surely many organisations transfer archives to hard drives and only check them once every 6-12 months.
Yet due to the pressures of technological obsolescence and the need to remain vigilant about file operability, coupled with the functional purpose of digital archives to be quickly accessible in comparison with tape that can only be played back linearly, such energy consumption does seem fairly inescapable for large institutions in an increasingly voracious, 24/7 information culture. Of course the issue of obsolescence will undoubtedly affect super-storage-data tape cartridges as well. Technology does not stop innovating – it is not in the interests of the market to do so.
Perhaps more significantly, the archive world has not yet developed standards that address the needs of digital information managers. Henry Newman’s presentation at the Designing Storage Architectures 2013 conference explored the difficulty of digital data management, precisely due to the lack of established standards:
‘There are some proprietary solutions available for archives that address end to end integrity;
There are some open standards, but none that address end to end integrity;
So, there are no open solutions that meet the needs of [the] archival community.’
He goes on to write that standards are ‘technically challenging’ and require ‘years of domain knowledge and detailed understanding of the technology’ to implement. Worryingly perhaps, he writes that ‘standards groups do not seem to be coordinating well from the lowest layers to the highest layers.’ By this we can conclude that the lack of streamlined conversation around the issue of digital standards means that effectively users and producers are not working in synchrony. This is making the issue of digital information management a challenging one, and will continue to be this way unless needs and interests are seen as mutual.
For the lay (wo)man this basically translates as the capacity to develop computer memory stored on hard drives. We are used to living in a consumer society where new improved gadgets appear all the time. Devices are getting smaller and we seem to be able buy more storage space for cheaper prices. For example, it now costs under £100 to buy a 3TB hard drive, and it is becoming increasingly more difficult to purchase hard drives which have less than 500GB storage space. Compared with last year, a 1TB hard drive was the top of the range and would have probably cost you about £100.
Does my data look big in this?
Yet the presentation from Gary Decad suggests we are reaching a plateau with this kind of storage technology – infinite memory growth and reduced costs will soon no longer be feasible. The presentation states that ‘with decreasing rates of areal density increases for storage components and with component manufactures reluctance to invest in new capacity, historical decreases in the cost of storage ($/GB) will not be sustained.’
Where does that leave us now? The resilience of tape as an archival solution, the energy implications of digital hard drive storage, the lack of established archival standards and a foreseeable end to cheap and easy big digital data storage, are all indications of the complex and confusing terrain of information management in the 21st century. Perhaps the Clipper report offers the most grounded appraisal: ‘the best solution is really a blend of disk and tape, but – for most uses – we believe that the vast majority of archived data should reside on tape.’ Yet it seems until the day standards are established in line with the needs of digital information managers, this area will continue to generate troubling, if intriguing, conundrums.
Even relatively recent born-digital formats like Digital Betacam (or DigiBeta, as it’s often referred to) should be viewed as a potentially obsolete format. This Standard Definition (SD) format while very popular for many years is not the preferred delivery format now the industry has embraced High Definition (HD).
When serviced these machines are very reliable and would be worked hard in a production environment. Designed to be serviced with little expense spared these were some of Sony’s most expensive decks and even if second hand values of machines have dropped recently, new spares have not. As with most video formats though as they become less popular the spares availability will become a problem as parts inventory dry up. One day and it may not be that far away a popular format like DigiBeta will become a threatened, obsolete format.
Digital Betacam recorders were introduced in 1993, superseding the Betacam and Betacam SP, while costing significantly less, and being dramatically smaller than (!), the D-1.
We are particularly pleased with this machine because there are relatively low hours on its original head drum (1000 hours). The average headlife for this format is up to three times that or more, depending on the environment it was used in.
If the machine was used in a heavy production environment, for example, it would be constantly drawing in air to cool the electronics and, potentially, large amounts of dust and debris with it. This is one of the factors affecting head life.
Part of the service kit installed on the DigiBeta is designed to counter such damage because it allows you to replace the filters around the head drum area should they become clogged.
The big problem, as with so many of these machines, is acquiring relevant parts to ensure they can be serviced when they break down. Spare parts for DigiBeta machines can be expensive, costing several thousand pounds for a replacement head drum.
This machine has needed some work recently to keep it running smoothly. The loading gear had split which meant it couldn’t load tapes and gave reel motor errors. These were fixed easily by replacing the broken parts. After these repairs were completed the picture was still however displaying errors. This was because the bearing on the pinch roller was worn resulting in too much movement in the tape path. With the problem diagnosed a new pinch roller was installed and our new machine is working beautifully!
In 2005 UNESCO (United Nations Education, Scientific and Cultural Organisation) decided to commemorate 27 October as World Audiovisual Heritage Day. The theme for 2013 was ‘Saving Our Heritage for the Next Generation’. Even though we are a day late, we wanted to write a post to mark the occasion.
UNESCO argue that audiovisual heritage is a unique vehicle for cultural memory because it can transcend ‘language and cultural boundaries’ and appeal ‘immediately to the eye and the ear.’
World Audiovisual Heritage Day aims to recognise both the value and vulnerability of audiovisual heritage. It aims to raise awareness that much important material will be lost unless ‘resources, skills, and structures’ are established and ‘international action’ taken.
Many important records of the 20th and 21st century are captured on film, yet digitally preserving this material generates specific problems, which we often discuss on this blog. Andrea Zarza Canova emphasises this point on the British Library’s blog:
‘World Day for Audiovisual Heritage is an important moment to celebrate and draw attention to the efforts currently being made in audiovisual preservation. But the story doesn’t end here as the digital environment raises its own preservation challenges concerning the ephemerality of websites and digital formats. Saving our heritage for the next generation involves engaging with the ongoing complexities of preservation in a rapidly changing environment.’
World Audiovisual Heritage Day is an ideal opportunity to delve into UNESCO’s Memory of the World collection whose audiovisual register features rare footage including photo and film documentation of Palestinian refugees, footage of Fritz Lang’s motion picture Metropolis (1927), documentary heritage of Los olvidados (“The Young and the Damned”), made in 1950 by Spanish-Mexican director Luis Buñuel, documentary heritage of Aram Khachaturian the world renowned Armenian composer and many others. Of the 301 items in the Memory of the World collection, 57 are audiovisual or have significant audiovisual elements.
Digital preservation is central to our work at the Greatbear. We see ourselves as an integral part of the wider preservation process, offering a service for archive professionals who may not always have access to obsolete playback machines, or expert technical knowledge about how best to transfer analogue tape to digital formats. So if you need help with a digitisation project why not get in touch?
UNESCO would surely approve of our work because we help keep the audiovisual memory of the world alive.
Most customers who send us tape to digitise own the copyright of their recording: it is material they have created themselves, be it music, spoken word or film.
Occasionally customers are not so sure if they own the full copyright to their recordings. This is because a single piece of work can have multiple copyright holders.
For example, films and songs can have many different contributors, such as the person who made the recording, the songwriter and performers. There are performing rights royalties which are paid to a songwriter, composer or publisher whenever their music is played or performed in any public space or place; mechanical rights royalties which are paid to the songwriter, composer or publisher when music is reproduced as a physical product or for broadcast or online, and performers rights royalties which are paid to the people performing on the record. It can seem like a bit of a minefield, and you do have to be really careful, particularly if want to re-publish the works in a commercial context.
A collection of tapes that include original recordings made by the customer
The simple truth is, if you do not have full permission of all copyright holders, you would break the law if you digitised a tape and re-published it commercially.
Copyright, Intellectual Property and Digital Preservation is a tricky area to negotiate. Currently ‘there is still no exception in UK law for preservation copying. For materials which are still in copyright, permissions should be sought from copyright holders prior to any copying being done. This area is under consideration though with museums, libraries and archives lobbying for change’ (Jisc Digital Media).
‘In “Chapter III: Acts permitted in relation to copyright works”, the Copyright Designs and Patents Act 1988 provides for a series of permissible activities that would otherwise be barred for breach of a rights holder’s exclusive rights. These include the “fair dealing provisions” which, for example, state that making transient copies is an integral and essential part of certain technological processes (s.28), and using all or part of a copyright work for non-commercial research or private study (s.29), criticism or review, or reporting current events (s.30), do not constitute infringements’ (11).
Clearly copyright law as it stands places immense restrictions in a digital environment where copying and sharing all kinds of things is pretty much the norm. What are the arguments then for changing copyright laws? In Imagine there is no copyright and cultural conglomerates too by Joost Smiers and Marieke Van Schinjdel, published by the Institute of Network Cultures‘ Theory on Demand series, they argue that removing copyright from cultural products will ensure that ‘our past and present heritage of cultural expression, our public domain of artistic creativity and knowledge will no longer be privatised’ (6).
Making cultural heritage publicly available is an argument for transforming current copyright laws across the range of political positions. While Smiers and Van Schinjdel interpret privatisation embedded in copyright law as linked to commercial power, the implicit argument in the DPC report is that opening up current restrictions can only be good for business. In this particular domain we see how the value of archival information has shifted in the digital landscape, so that it is increasingly seen as a resource through which money can be made.
A transformation of copyright laws would not necessarily lead to a weakening of commercial interests as Smiers and Van Schinjdel speculate, but would most probably enable the re-use of information across a range of profit and profit-making initiatives. Charlesworth insists we are ‘clinging to copyright practices that reflect outdated business models rather than attempting to establish new practices to address the prevailing mixed analogue/digital environment’ (7).
The digital information revolution has required all sectors of society to change how they relate to, use, record, save and consume information. While we have all become, to a lesser or more degree, record keepers, this brief survey of copyright law may help us appreciate the challenges professional archivists face in negotiating this complex area. After all, ‘life would be much simpler for archivists if the law relating to the preservation of copyright works in general, and digital works in particular, was both clarified and, where necessary, extended to permit more robust strategies for collection, preservation and reuse of copyright works’ (5).
We recently digitised some VHS tapes from when Bristol-based band Meet Your Feet performed on HTV in 1990. Meet Your Feet
‘formed in 1988 as a result of three of the women getting together to start a women’s music workshop, Meet Your Feet played its first gig in June 1988, when asked to get a set together for a Benefit Gig against section 28. This gig was so successful that the band decided to stay together and gradually the original line-up of the early years of the band evolved: Carol Thomas, vocals; Diana Milstein, founder member, bass and lyricist; Diggy, percussion; Heie Gelhaus, founder member, keyboards and songwriter; Julie Lockhart, vocals; Karen Keen, sax; Sue Hewitt, founder member, drums and songwriter; Vicki Burke, sax’ (taken from the Women’s Liberation Music Archive).
During the 80s the band achieved great success and performed at prestigious festivals such as Glastonbury and WOMAD, as well as appearing on Radio 4’s Women’s Hour. They played together until 1992 before disbanding, reformed in 2010 and continue to play shows in Bristol and beyond. Meet Your Feet’s style, which draws from Latin, Jazz and Soul influences, interspersed with passionate, upbeat political lyrics, align them with other ‘women’s music’ bands from the 1980s, such as The Guest Stars and Hi-Jinx.
The video clip we digitised is interesting because it indicates how novel women’s bands were in 1990.
After the band finish performing their new single, they take part in a short interview where they are asked:
‘Its an obvious question, but I am going to ask it, why all women?’
Julie Lockhart, one of the singers, responds wittily, but not without a tinge of bewilderment, ‘Um, we were born that way!’
Can you imagine an all male group being asked a similar question in a television interview, either now or in the early 1990s?! It just wouldn’t happen because no one notices if all the members of a group are male, it just seems completely normal.
The interview goes on to emphasise gender issues, rather than focus on other aspects, such as themes in their music or that it is a large group (there are nine people in the band after all, which is a lot!)
This is not a criticism of the interviewer’s questions as such. Yet the fact it was necessary to asks them about their gender speaks volumes about how surprising it was to see women playing music together. The interview continues as follows:
Presenter: Are there any real advantages to being an all female group?
Sue Hewitt: We listen to each other more, and spin ideas of each other a lot more easily
Julie Lockhart: We giggle a lot more
Presenter: Do you row a lot because you are on the road, its a hard life isn’t it, very intense?
Julie Lockhart: No, that’s the obvious difference we never row!
Presenter: Do you find it hard to be taken seriously by men who come to see an all girl band?
Sue Hewitt: Well no, not all the time. I think initially some men take the view of ‘oh well, its just a bunch of girls on stage’ but when we get up there and start playing they think, ohhh [they can play as well]
It is frustrating that such questions had to be asked, and maybe they wouldn’t be now – although it is still often the case that in music, as in other areas of cultural life, women’s gender is marked, while male gender is not. We have all heard, for example, the phrase ‘female-fronted band’. When do we ever hear of bands that are ‘male-fronted’?
It is really valuable to have access to recordings such as those of Meet Your Feet, not only as a documentation of their performances, but also to demonstrate the attitudes and assumptions that women faced when they participated in a male dominated cultural field.
It is also good to know that Meet Your Feet are still performing and undoubtedly upsetting a few stereotypes and expectations along the way, so make sure you catch them at a show soon!
‘The participatory art installation that I called “Clews” took place in “The White Room”, a bookable studio space at the Slade School of Art, over three days in 1979. People entering the space found that the room had been divided in half by a wooden wall that they could not see beyond, but they could enter the part nearest the entrance. In that half of the room there was a video monitor on a table with a camera above it pointing in the direction of anyone viewing the screen. There was also some seating so that they could comfortably view the monitor. Pinned to the wall next to the monitor was a notice including cryptic instructions that referred to part of a maze that could be seen on the screen. Participants could instruct the person with the video camera to change the view by giving simple verbal instructions, such as ‘up’, “down”, “left”, “right”, “stop”, etc. until they found a symbol that indicated an “exit”.’
My plan was to edit the video recordings of the event into a separate, dual screen piece but it was too technically challenging for me at the time. I kept the tapes though, with the intention of completing the piece when time and resources became available. This eventually happened in 2012 when, researching ways to get the tapes digitized, I discovered Greatbear in Bristol. They have done a great job of digitizing the material and this is the first version of piece I envisaged all those years ago.’
Metadata is data about data. Maybe that sounds pretty boring, but archivists love it, and it is really important for digitisation work.
As mentioned in the previous post that focused on the British Library’s digital preservation strategies, as well as manyotherfeatures on thisblog, it is fairly easy to change a digital file without knowing because you can’t see the changes. Sometimes changing a file is reversible (as in non-destructive editing) but sometimes it is not (destructive editing). What is important to realise is changing a digital file irrevocably, or applying lossy instead of lossless compression, will affect the integrity and authenticity of the data.
What is perhaps worse in the professional archive sector than changing the structure of the data, is not making a record of it in the metadata.
Metadata is a way to record all the journeys a data object has gone through in its lifetime. It can be used to highlight preservation concerns if, for example, a file has undergone several cycles of coding and decoding that potentially make it vulnerable to degradation.
‘technical data (info on resolution, image size, file format, version, size), structural metadata (describes how digital objects are put together such as a structure of files in different folders) and descriptive (info on title, subject, description and covering dates) with each type providing important information about the digital object.’
As the previous blog entry detailed, digital preservation is a dynamic, constantly changing sector. Furthermore, digital data requires far greater intervention to manage collections than physical objects and even analogue media. In such a context data objects undergo rapid changes as they adapt to the technical systems they are opened by and moved between. This would produce, one would speculate, a large stream of metadata.
What is most revealing about metadata surrounding digital objects, is they create a trail of information not only about the objects themselves. They also document our changing relationship to, and knowledge about, digital preservation. Metadata can help tell the story about how a digital object is transformed as different technical systems are adopted and then left behind. The marks of those changes are carried in the data object’s file structure, and the metadata that further elaborate those changes.
Like those who preserve physical heritage collections, a practice of minimal intervention is the ideal for maintaining both the integrity and authenticity of digital collections. But mistakes are made, and attempts to ‘clean up’ or otherwise clarify digital data do happen, so when they do, it is important to record those changes because they help guide how we look after archives in the long term.
In a blog post a few weeks ago we reflected on several practical and ethical questions emerging from our digitisation work. To explore these issues further we decided to take an in-depth look at the British Library’s Digital Preservation Strategy 2013-2016 that was launched in March 2013. The British Library is an interesting case study because they were an ‘early adopter’ of digital technology (2002), and are also committed to ensuring their digital archives are accessible in the long term.
Making sure the UK’s digital archives are available for subsequent generations seems like an obvious aim for an institution like the British Library. That’s what they should be doing, right? Yet it is clear from reading the strategy report that digital preservation is an unsettled and complex field, one that is certainly ‘not straightforward. It requires action and intervention throughout the lifecycle, far earlier and more frequently than does our physical collection (3).’
The British Library’s collection is huge and therefore requires coherent systems capable of managing its vast quantities of information.
‘In all, we estimate we already have over 280 terabytes of collection content – or over 11,500,000 million items – stored in our long term digital library system, with more awaiting ingest. The onset of non-print legal deposit legislation will significantly increase our annual digital acquisitions: 4.8 million websites, 120,000 e-journal articles and 12,000 e-books will be collected in the first year alone (FY 13/14). We expect that the total size of our collection will increase massively in future years to around 5 petabytes [that’s 5000 terabytes] by 2020.’
All that data needs to be backed up as well. In some cases valuable digital collections are backed up in different locations/ servers seven times (amounting to 35 petabytes/ 3500 terabytes). So imagine it is 2020, and you walk into a large room crammed full of rack upon rack of hard drives bursting with digital information. The data files – which include everything from a BWAV audio file of a speech by Natalie Bennett, leader of the Green Party after her election victory in 2015, to 3-D data files of cunieform scripts from Mesopotamia, are constantly being monitored by algorithms designed to maintain the integrity of data objects. The algorithms measure bit rot and data decay and produce further volumes of metadata as each wave of file validation is initiated. The back up systems consume large amounts of energy and are costly, but in beholding them you stand in the same room as the memory of the world, automatically checked, corrected and repaired in monthly cycles.
Such a scenario is gestured toward in the British Library’s long term preservation strategy, but it is clear that it remains a work in progress, largely because the field of digital preservation is always changing. While the British Library has well-established procedures in place to manage their physical collections, they have not yet achieved this with their digital ones. Not surprisingly ‘technological obsolescence is often regarded as the greatest technical threat to preserving digital material: as technology changes, it becomes increasingly difficult to reliably access content created on and intended to be accessed on older computing platforms.’ An article fromThe Economist in 2012 reflected on this problem too: ‘The stakes are high. Mistakes 30 years ago mean that much of the early digital age is already a closed book (or no book at all) to historians.’
There are also shorter term digital preservation challenges, which encompass ‘everything from media integrity and bit rot to digital rights management and metadata.’ Bit rot is one of those terms capable of inducing widespread panic. It refers to how storage media, in particular optical media like CDs and DVDs, decay over time often because they have not been stored correctly. When bit rot occurs, a small electric charge of a ‘bit’ in memory disperses, possibly altering program code or stored data, making the media difficult to read and at worst, unreadable. Higher level software systems used by large institutional archives mitigate the risk of such underlying failures by implementing integrity checking and self-repairing algorithms (as imagined in the 2020 digital archive fantasy above). These technological processes help maintain ‘integrity and fixity checking, content stabilisation, format validation and file characterisation.’
300 years, are you sure?
Preservation differences between analogue and digital media
The British Library isolate three main areas where digital technologies differ from their analogue counterparts. Firstly there is the issue of ‘proactive lifestyle management‘. This refers to how preservation interventions for digital data need to happen earlier, and be reviewed more frequently, than analogue data. Secondly there is the issue of file ‘integrity and validation.’ This refers to how it is far easier to make changes to a digital file without noticing, while with a physical object it is usually clear if it has decayed or a bit has fallen off. This means there are greater risks to the authenticity and integrity of digital objects, and any changes need to be carefully managed and recorded properly in metadata.
Finally, and perhaps most worrying, is the ‘fragility of storage media‘. Here the British Library explain:
‘The media upon which digital materials are stored is often unstable and its reliability diminishes over time. This can be exacerbated by unsuitable storage conditions and handling. The resulting bit rot can prevent files from rendering correctly if at all; this can happen with no notice and within just a few years, sometimes less, of the media being produced’.
A holistic approach to digital preservation involves taking and assessing significant risks, as well as adapting to vast technological change. ‘The strategies we implement must be regularly re-assessed: technologies and technical infrastructures will continue to evolve, so preservation solutions may themselves become obsolete if not regularly re-validated in each new technological environment.’
Establishing best practice for digital preservation remains a bit of an experiment, and different strategies such as migration, emulation and normalisation are tested to find out what model best helps counter the real threats of inaccessibility and obsolescence we may face in 5-10 years from now. What is encouraging about the British Library’s strategic vision is they are committed to ensuring digital archives are accessible for years to come despite the very clear challenges they face.
We have already written about noise reduction this week, but did so without acknowledging the life of Ray Dolby, one of the inventors of video tape recording while working at Ampex and the inventor and founder of Dolby Noise Reduction, who died on 12 September 2013.
‘His noise-reduction system worked by applying a pre-emphasis to the audio recording, usually boosting the quieter passages. The reverse process was used on playback. Removing the boost – lowering the level – also removed most of the tape hiss that accompanied all analogue recordings. Of course, people did not care how it worked: they could hear the difference.’
Dolby managed to solve a clear problem blighting analogue tape recording: the high frequency noise or tape hiss inherent when recording on magnetic tape.
Like many professional recording studios from the 1960s onwards, the Great Bear Studio uses the Dolby A noise-reduction system that we use to play back Dolby A encoded tape. On the Dolby A the input signal is split into four individual frequency bands and provided 10 dB of broadband noise reduction overall.
We also have a Dolby SR system that was introduced in 1986 to improve upon analogue systems and in some cases surpass rapidly innovating digital sound technologies. Dolby SR maximises the recorded signal at all times using a complex series of filters that change according to the input signal and can account for up to 25dB noise reduction.
In a 2012 report entitled ‘Preserving Sound and Moving Pictures’ for the Digital Preservation Coalition’s Technology Watch Report series, Richard Wright outlines the unique challenges involved in digitising audio and audiovisual material. ‘Preserving the quality of the digitized signal’ across a range of migration processes that can negotiate ‘cycles of lossy encoding, decoding and reformatting is one major digital preservation challenge for audiovisual files’ (1).
Wright highlights a key issue: understanding how data changes as it is played back, or moved from location to location, is important for thinking about digitisation as a long term project. When data is encoded, decoded or reformatted it alters shape, therefore potentially leading to a compromise in quality. This is a technical way of describing how elements of a data object are added to, taken away or otherwise transformed when they are played back across a range of systems and software that are different from the original data object.
To think about this in terms which will be familiar to people today, imagine converting an uncompressed WAV into an MP3 file. You then burn your MP3s onto a CD as a WAV file so it will play back on your friend’s CD player. The WAV file you started off with is not the same as the WAV file you end up with – its been squished and squashed, and in terms of data storage, is far smaller. While smaller file size may be a bonus, the loss of quality isn’t. But this is what happens when files are encoded, decoded and reformatted.
Subjecting data to multiple layers of encoding and decoding does not only apply to digital data. Take Betacam video for instance, a component analogue video format introduced by SONY in 1982. If your video was played back using composite output, the circuity within the Betacam video machine would have needed to encode it. The difference may have looked subtle, and you may not have even noticed any change, but the structure of the signal would be altered in a ‘lossy’ way and can not be recovered to it’s original form. The encoding of a component signal, which is split into two or more channels, to a composite signal, which essentially squashes the channels together, is comparable to the lossy compression applied to digital formats such as mp3 audio, mpeg2 video, etc.
A central part of the work we do at Greatbear is to understand the changes that may have occurred to the signal over time, and try to minimise further losses in the digitisation process. We use a range of specialist equipment so we can carefully measure the quality of the analogue signal, including external time based correctors and wave form monitors. We also make educated decisions about which machine to play back tapes in line with what we expect the original recording was made on.
If we take for granted that any kind of data file, whether analogue or digital, will have been altered in its lifetime in some way, either through changes to the signal, file structure or because of poor storage, an important question arises from an archival point of view. What do we do with the quality of the data customers send us to digitise? If the signal of a video tape is fuzzy, should we try to stabilise the image? If there is hiss and other forms of noise on tape, should we reduce it? Should we apply the same conservation values to audio and film as we do to historic buildings, such as ruins, or great works of art? Should we practice minimal intervention, use appropriate materials and methods that aim to be reversible, while ensuring that full documentation of all work undertaken is made, creating a trail of endless metadata as we go along?
Do we need to preserve the ways magnetic tape, optical media and digital files degrade and deteriorate over time, or are the rules different for media objects that store information which is not necessarily exclusive to them (the same recording can be played back on a vinyl record, a cassette tape, a CD player, an 8 track cartridge or a MP3 file, for example)? Or should we ensure that we can hear and see clearly, and risk altering the original recording so we can watch a digitised VHS on a flat screen HD television, in line with our current expectations of media quality?
Richard Wright suggests it is the data, rather than operating facility, which is the important thing about the digital preservation of audio and audiovisual media.
‘These patterns (for film) and signals (for video and audio) are more like data than like artefacts. The preservation requirement is not to keep the original recording media, but to keep the data, the information, recovered from that media’ (3).
Yet it is not always easy to understand what parts of the data should be discarded, and which parts should kept. Audiovisual and audio data are a production of both form and content, and it is worth taking care over the practices we use to preserve our collections in case we overlook the significance of this point and lose something valuable – culturally, historically and technologically.
Today is the first day of iPres 2013, the 10th international conference on the preservation of digital objects held in Lisbon, Portugal. To mark the occasion we want to reflect on an issue that is increasingly important for the long term management of digital data: curation.
Anyone who has lived through the digital transition in the 21st century surely cannot ignore the information revolution they have been part of. In the past ten years, vast archives of analogue media have been migrated to digital formats and everyday we create new digital information that is archived and distributed through networks. Arcomen, who are running a workshop at iPres on ‘Archiving Community Memories’, describe how
‘in addition to the “common” challenges of digital preservation, such as media decay, technological obsolescence, authenticity and integrity issues, web preservation has to deal with the sheer size and ever-increasing growth and change rate of Web data. Hence, selection of content sources becomes a crucial and challenging task for archival organizations.’
As well as the necessary and sometimes difficult choices archival organisations have to make in the process of collecting an archive, there is then the issue of what to do with your data once it has been created. This is where the issue of digital curation comes in.
Screenshot of the SONY website from 1996
Traditionally, the role of the curator is to ‘take care’ and interpret collections in an art gallery or a museum. In contemporary society, however, there is an increasing need for people to curate collections that are exclusively digital, and can only be accessed through the web. Part of any long term digitisation strategy, particularly if an archive is to be used for education or research purposes, should therefore factor in plans and time for curation.
Curation transforms a digital collection from being the equivalent of a library, which may be searchable, organised and catalogued, into something more akin to an exhibition. Curation helps to select aspects of an archive in order to tell deliberate stories, or simply help the user navigate content in a particular way. Curating material is particularly important if an archive deals with a specialist subject that no one knows about because visitors often need help to manoeuvre large amounts of complex information. Being overwhelmed by content on the internet is an often cited expression, but ensuring digital content is curated carefully means it is more likely that people visiting your site will be able to cope with what they find there, and delve deeper into your digitsed archival treasures.
Like all things digital, there is no one steadfast or established guidelines for how to ensure your collection is curated well. The rapid speed that technology changes, from preferred archival formats, software to interface design, mean that digital curation can never be a static procedure. New multiple web authoring tools such as zeega, klynt and 3WDOC will soon become integrated into web design in a similar fashion to the current Web 2.0 tools we use now, therefore creating further possibilities for the visual, immersive and interactive presentation of digital archive material.
Screenshot of the Fostex website from Dec 1998
Curation is an important aspect of digital preservation in general because it can facilitate long term use and engagement with your collection. What may be lost when archive sites become pruned and more self-consciously arranged is the spontaneous and sometimes chaotic experience of exploring information on the web.
Ultimately though, digital curation will enable more people to navigate archival collections in ways that can foster meaningful, transformative and informative encounters with digitised material.
The Archive Trust for Research in Mathematical Sciences and Philosophy holds an extensive collection of audio and video recordings on subjects in mathematics, physics and philosophy, particularly the philosophy and foundations of mathematics and the exact sciences recorded since the early 1970s.
The website explains further the rationale for collecting the recordings:
Such recordings allow historians of science and mathematics to form a better appreciation of the background to the emergence of new ideas; and also of the complex pattern formed by “roads not taken” – ideas which for whatever reason were laid aside, or apparently subsumed in other developments. Those ideas may later re-emerge in ways yielding a new perspective on those developments. Such a rich archive of primary oral source material naturally aids historical study of the Sciences and the conceptual and philosophical questions to which they give rise.
The project started in 1973 when Michael recorded lectures, seminars and courses relating to Maths and Philosophy when he was a doctoral student. The early recordings were made in Oxford, London and Cambridge and were done on an enthusiastic, if amateur basis. In the 1980s and 1990s the recording process became more systematic, and more video recordings were taken. The archive is still collecting material, and Michael often travels to conferences and lectures to record contemporary debates in the field, as he is this week when he travels to Warsaw for Samuel Eilenberg Centenary conference (there are recordings of Eilenberg’s lectures and an interview collected in the archive).
What started as a hobby for Michael has now become a full time commitment. The archive contains a staggering 37,000 recordings, those he made and ones solicited from other individuals. They include recordings of figures such as Imre Lakatos, Ilya Prigogine, contemporary philosopher Alain Badiou and many more.
The majority of recordings from 1973-2003 were recorded on audio cassette format, although some were done on reel-to-reel recorders. Many of these recordings remain on analogue tape, and the biggest challenge for the archive is now to find the funds to migrate several thousand hours of recordings to digital format.
The archive also track downs and publishes existing material that may be collected in other archives, or are stored in people’s personal collections. For Michael the biggest revelation in constructing the archive was finding out about the amount of material people have that are sitting in the back of their cupboards. This is either because people have forgotten they exist, or because they simply do not known what to do with them.
The archive became a charitable trust in 2008 and names among its trustees English mathematical physicist and philosopher Sir Roger Penrose, and Martin Rees, former Master of Trinity College and Emeritus Professor of Cosmology at the University of Cambridge and President of the Royal Society.
Its an exciting, and transitional, time for the archive as it plans to take its next steps. In the coming years there are plans to develop the website through uploading ‘born digital’ information, attain funds for wholesale digitisation of tape and paper resources and continue to collect recordings. This ambitious project is well on its way to becoming a vital and unique contribution to the subject, and will interest many other people who are simply curious about these rich and complex topics.
Often when we think about the reasons to digitise magnetic tape collections we are considering the future. We digitise to make material accessible so it can be used again, or to preserve it so subsequent generations can benefit or learn from it. But how sustainable is digitisation and digital technology? What is the ecological impact of the widespread and breathtakingly fast adoption of digital technologies since the late 1990s?
At an everyday, consumer level, the use of digital technologies comes with real human and environmental costs, as Professor Toby Miller and Professor Richard Maxwell demonstrate in a recent article in The Guardian. They argue that the very metaphors we use to describe digital media – ‘virtual,’ ‘cloud’, ‘streams’ and ‘mobiles’ – dangerously obscure the fact they come from materials, such as the minerals Tatalun, Tungsten, Tin and Gold, and cover up the exploitative labour conditions, and war torn situations from which they are extracted:
‘Suggestions that we live in a dematerialised world are not only exaggerated; they are doing more harm than good. One person’s cloud is another’s pollution, and one person’s mobile is another’s enslavement. From electronic waste to conflict minerals, the new media leave an indelible mark on bodies and the Earth they inhabit.’
The extent of violence and exploitation that lie at the end of the digital supply chain is hardly a secret. At a consumer level there seems to be very little resistance to the use of mobile digital devices, probably because our very social existence is dependent upon them in a culture where media is pervasive. It is not easy to opt out, and what would you do if you did?
As heavy users of digital technologies we walk with our heads in the clouds, so to speak, unable to access the wider environmental impact of our actions. This impact is intensified by the pressure to continually upgrade our devices, as Dr Chris Priest writes,
‘the regularity with which you replace a device becomes more important in determining the overall footprint of the device. If we take a hypothetical device with a 50% use footprint, and replace it after two years rather than three, then it will increase our overall footprint by 25%. Of course, new devices might be becoming increasingly efficient and this could offset the increase to some extent. Though even if the new device used no power, it could not offset it completely.’
Yet these are speculations not empirical fact. It is hard to know concretely what the environmental consequences of becoming immediate adopters of the latest (fastest, smallest, bestest) digital technologies are. One thing is certain, new goods will appear and people will be told they can’t live without them. This is how an economy driven by innovation works.
Thinking about the uptake of digital technologies at an institutional level, it is clear that within a technological climate pre-disposed to the production of ‘digital waste’ and obsolescence, the mismanagement of energy resources in order to keep digital data ‘alive’ (that is useable, accessible) is a real possibility. One only need turn to the financial and technological waste produced from the BBC’s Digital Media Initiative (DMI) to confirm that the creation of technical systems devised to manage large digital archives are not moving at the same relentless speed as the neoliberal market.
Which begs the question: can there be an ecological solution to the problem of digitisation, and the use of digital technologies in an innovation/ obsolescence economy? Can digitisation ever be energy efficient, non-exploitative and flexible enough to cope with the technological changes that will inevitably happen? What would a sustainable and ethical approach to digital information management look like?
As our world gets increasingly networked these are pressing questions effecting everyone. And clearly understanding the wider impact of the use of technology on people and the earth is a serious issue, usually forgotten when scrolling through data feeds in a voracious, but often distracted, manner. These are admittedly big questions and we welcome comments, links and ideas on how to answer them.
As keen hoarders of mechanical waste from the analogue era who are passionate about making data accessible in digital form, we are contributing to a world that places unprecedented value on technological information.
Need this, however, always be at the expense of people and the world we share as currently it seems to be?
We have recently been sent a Sony V62 high density video tape by Barrie Hesketh. Barrie has had an active career in theatre and in 1966 he set up the Mull Little Theatre on the Isle of Mull off the West Coast of Scotland with his late wife Marianne Hesketh. Specialising in what Barrie calls the ‘imaginative use of nothing’ they toured the UK, Germany and Holland and gained a lot of publicity world wide in the process. Both Marianne and Barrie were awarded MBEs for their services to Scottish Theatre.
You can read a more detailed history of the Mull Little Theatre in this book written by Barrie.
Panasonic VTR NV-8030 EIAJ ½” reel to reel video recorder
The video tape Barrie sent us came from when he and Marianne were working as actors in residence at Churchill College at Cambridge University. Barrie and Marianne had what Barrie described as ‘academic leanings,’ gained from their time as students at the Central College of Speech and Drama in London.
In a letter Barrie sent with the tape he wrote:
‘I own a copy of a video tape recording made for me by the University of Cambridge video unit in 1979. I was researching audience/actors responses and the recording shows the audience on the top half of the picture, and the actors on the bottom half – I have not seen the stuff for years, but have recently been asked about it.’
While audience research is a fairly common practice now in the Creative Arts, in 1979 Barrie’s work was pioneering. Barrie was very aware of audience’s interests when he performed, and was keen to identify what he calls ‘the cool part’ of the audience, and find out ways to ‘warm them up.’
Recording audience responses was a means to sharpen the attention of actors. He was particularly interested in the research to identify ‘includers’. These were individuals who influenced the wider audience by picking up intentions of the performers and clearly responding. The movement of this individual (who would look around from time to time to see if other people ‘got it’), would be picked up in the peripheral vision of other audience members and an awareness gradually trickled throughout. Seeing such behaviour helped Barrie to understand how to engage audiences in his subsequent work.
Barrie’s tape would have been recorded on one of the later reel-to-reel tape machines that conformed to the EIAJ Standard.
The EIAJ-1 was developed in 1969 by the Electronic Industries Association of Japan. It was the first standardized format for industrial/non-broadcast video tape recording. Once implemented it enabled video tapes to be played on machines made by different manufacturers.
Prior to the introduction of the standard, tapes could not be interchanged between comparable models made by different manufacturers. The EIAJ standard changed all this, and certainly makes the job of transferring tapes easier for us today! Imagine the difficulties we would face if we had to get exactly the right machine for each tape transfer. It would probably magnify the problem of tape and machine obsolescence effecting magnetic tape collections.
In the Greatbear Studio we have the National Panasonic Time Lapse VTR NV-8030 and Hitachi SV-640.
Like Ampex tapes, all the Sony EIAJ tape tend to suffer from sticky shed syndrome caused by absorption of moisture into the binder of the tape. Tapes need to be dehydrated and cleaned before being played back, as we did with Barrie’s tape.
The tape is now being transferred and Barrie intends to give copies to his sons. It will also be used by Dr Richard Trim in an academic research project. In both cases it is gratifying to give the these video tapes a new lease of life through digitisation. No doubt they will be of real interest to Barrie’s family and the wider research community.
In a recent blog article on the Presto Centre website, Richard Wright argues that ‘the audiovisual collections of the 20th century were analogue, and we are now at a critical time for considering the digital future of that analogue content.’ He goes on to say, emphatically:
‘All analogue audio and video formats are obsolete. Digital content walks through walls, travels at the speed of light, can be in many places at the same time, and can (with care) be perfectly copied, again and again. So digitisation has become the solution to the obsolescence of all analogue audio and video formats.’
Although careful not to make too clinical a statement, he bookmarks 15 April 2023 as the date when analogue obsolescence really kicks in.
A major problem is finding spare parts for machines after manufacturers stop producing them. Many components were made according to very precise specifications that are hard to make from scratch. When machines and their parts wear out it will therefore be difficult, if not impossible, to keep them working.
This means that the cost of transfers will rise due to machine scarcity. At an institutional level this may lead to selective decisions about what gets digitised and what doesn’t.
Writing for music magazine The Wire, Numero Group’s Rob Sevier and Ken Shipley describe how ‘vinyl’s violent sales spike has been a lonely bright spot in what has been a 14 year deterioration in sales of recorded music’.
Yet the resilience of vinyl and other contemporary fringe uses of analogue media, such as the cassette tape and floppy disk, is not enough to stop the march of digitisation. For experts like Wright the digital future for the majority of people is inevitable, irresistible even, given how it enables collections to be open, replicable and accessible.
Yet committing to digital technologies as a preservation and access strategy does not solve our information problems, as we have been keen to stress on this blog. There is also a worrying lack of long term strategy for managing digital information, a problem which is ever more pronounced in film preservation where analogue tape is still marked as the original from which digital copies are made.
It is clear that the information we create, store and use is in transition. It probably always has been. The emergence of digital technologies has just made this a pressing issue, not only for large institutions, but for people as we go about our day to day lives.
‘Digitise now!!’ is Richard Wright’s advice – and of course we agree.
Digitising legacy and obsolete video formats in essence is simple but the technical details make the process more complex. Experience and knowledge are therefore needed to make the most appropriate choices for the medium.
The U-matic video format usually had two types of video output, composite and a y/c type connector that Sony named ‘Dub’. Originally designed as a higher quality method to make analogue ‘dubs’, or for connections in an edit suite, the Dub connector offers a higher performance signal path for the video signal.
It would make sense to use the higher quality dub output when digitising U-matic tapes but here lies the problem. Firstly the connector uses the larger 7 pin y/c type connector that can be quite hard to find connectors for.
Secondly and most significantly, the chrominance subcarrier frequency is not the standard PAL 4.43Mhz but down converted by U-matic recorders to 0.686Mhz for low band recordings and 0.984Mhz for high band recordings.
What this means in practice is that you’ll only get a monochrome image using the U-matic dub connector unless you can find a way to convert the chroma subcarrier frequency back to 4.43Mhz.
There are several solutions:
Convert this Dub signal chroma frequency using one of a few older Timebase Correctors / Frame Synchronisers from the U-matic era.
These are now rare and often have other other faults that would degrade the signal.
Take the Luma and Chroma signals at the correct frequency directly from certain test points on the circuit boards inside the machines.
This can work well but is a slightly ‘messy’ solution and makes it hard to swap machines around, which is a necessity with older hardware.
Convert the dub signal using a dedicated external dub – y/c converter circuit. This is our preferred solution that works well technically. It is flexible enough to swap around to different machines easily. It is also a relatively simple circuit that is easy to repair and doesn’t subject the video signal to unnecessary extra processing.
Below are two stills taken from a Apple ProRes recording from a Low Band PAL U-matic tape.
The first image is via the Dub connecter but converted to PAL Y/C.
The second images is via the Composite video out.
It’s clear from the images that there is more fine detail in the picture from the U-matic Dub version. The pattern / texture in the jacket and the texture and tone in the face is more detailed. In contrast, the version digitised through the Composite video connector has less noise but due to the extra encoding and decoding there is less detail and more ‘blurring’.
While less noise may be preferable in some instances, having the option to choose between these two is always better. It’s this kind of attention detail and investment in equipment and knowledge that we are proud of and makes us a preferred supplier of digitising services for U-matic video tape.
There are plenty of reflections on the Great Bear tape blog about the fragility of digital data, and the need to think about digitisation as part of a wider process of data migration your information will need to make in its lifetime.
We have also explored how fast moving technological change can sometimes compromise our capacity to construct long term strategies for the survival of digital data.
This why it is so important that organisations such as the Digital Preservation Coalition, founded in February 2002, articulate a vision that aims to make ‘digital memory accessible tomorrow.’ Their website goes on to say:
Our generation has invested as never before in digital resources and we’ve done so because of the opportunity they bring. They have grown in volume, complexity and importance to the point that our children are baffled by the inefficiencies of the analogue age. Pervasive, fluid and fragile: digital data is a defining feature of our age. Industry, commerce, government, law, research, health, social care, education, the creative industries, the heritage sector and private life depend on digital materials to satisfy ubiquitous information needs and expectations. Digital preservation is an issue which all organisations, particularly in the knowledge sector, will need to address sooner or later.
As providers of a digitisation service it is important for us to understand digitisation in line with the ideas articulated above. This means creating high quality, uncompressed files that will make it as easy as possible for data migrations to happen in the future should they need to.
Organisations such as the Digital Preservation Coalition are providing sensible advice and creating forums for learning and debate about the problems and possibilities of digital preservation.
These are two things that are needed as we come to navigate an information environment heavily populated by ‘pervasive, fluid and fragile’ digital data.
