Posts Tagged ‘Digital Video Tape’

Re-animating archives: Action Space’s V30H / V60H EIAJ 1/2″ video tapes

Wednesday, May 20th, 2015

One of the most interesting aspects of digitising magnetic tapes is what happens to them after they leave the Great Bear studio.

Often transfers are done for private or personal interest, such as listening to the recording of loved ones, or for straightforward archival reasons.

Yet in some cases material is re-used in a new creative project, thereby translating recordings within a different technical and historical context.

Walter Benjamin described such acts as the ‘afterlife’ of translation: ‘a translation issues from the original not so much for its life as from its afterlife […] translation marks their stage of continued life.’ [1]

A child stands on top of an inflatable structure, black and white image.

Stills from the Action Space tapes

So it was with a collection of ½ inch EIAJ SONY V30H and V60H video tapes that recently landed in the Great Bear studio which documented the antics of Action Space.

Part of the vanguard movement of radical arts organisations that emerged in the late 1960s, Action Space described themselves as ‘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.’ [2]

Such creative shape-shifting, which took its impulsive artistic action in a range of public spaces can so often be the enemy of documentation.

Yet Ken Turner, who founded Action Space alongside Mary Turner and Alan Nisbet, told me that ‘Super Eight film and transparency slides were our main documentation tools, so we were aware of recording events and their importance.’

Introduced in 1969, EIAJ 1/2″ was the first format to make video tape recording accessible to people outside the professional broadcast industry.

Action Space were part of this wave of audiovisual adoption (minor of course by today’s standards!)

After ‘accidentally’ inheriting a portapak recorder from the Marquis of Bath, Ken explained, Action Space ‘took the portapak in our stride into events and dramas of the community festivals and neighbourhood gatherings, and adventure playgrounds. We did not have an editing deck; as far as I can remember played back footage through a TV, but even then it had white noise, if that’s the term, probably it was dirty recording heads. We were not to know.’

Preservation issues

Yes those dirty recording heads make things more difficult when it comes to re-formatting the material.

While some of the recordings replay almost perfectly, some have odd tracking problems and emit noise, which are evidence of a faulty recorder and/or dirty tape path or heads. Because such imperfections were embedded at the time of recording, there is little that can be done to ‘clean up’ the signal.

Other problems with the Action Space collection arise from the chemical composition of the tapes. The recordings are mainly on Sony branded V30H and high density V60H tape which always suffer from binder hydrolysis. The tapes therefore needed ‘baking’ treatment prior to transfer usually (we have found) in a more controlled and longer way from Ampex branded tapes.

And that old foe of magnetic tape strikes again: mould. Due to being stored in an inappropriate environment over a prolonged period, many of the tapes have mould growth that has damaged the binder.

Despite these imperfections, or even because of them, Ken appreciates the unique value of these recordings: ‘the footage I have now of the community use reminds me of the rawness of the events, the people and the atmosphere of noise and constant movement. I am extremely glad to have these tapes transposed into digital footage as they vividly remind me of earlier times. I think this is essential to understanding the history and past experiences that might otherwise escape the memories of events.’

People sliding down an inflatable structure, joyful expressions on their faces.Historical translation

While the footage of Action Space is in itself a valuable historical document, the recordings will be subject a further act of translation, courtesy of Ken’s film maker son, Huw Wahl.

Fresh from the success of his film about anarchist art critic and poet Herbert Read, Huw is using the digitised tapes as inspiration for a new work.

This new film will reflect on the legacies of Action Space, examing how the group’s interventions can speak to our current historical context.

Huw told me he wants to re-animate Action Space’s ethos of free play, education and art in order ‘to question what actions could shape a democratic and creative society. In terms of the rhetoric of creativity we hear now from the arts council and artistic institutions, it’s important to look at where that developed from. Once we see how radical those beginnings really were, maybe we will see more clearly where we are heading if we continue to look at creativity as a commodity, rather than a potent force for a different kind of society.’

Inflatable action

Part of such re-animation will entail re-visiting Action Space’s work with large inflatable structures, or what Ken prefers to call ‘air or pneumatic structures.’

Huw intends to make a new inflatable structure that will act as the container for a range of artistic, academic, musical and nostalgic responses to Action Space’s history. The finished film will then be screened inside the inflatable, creating what promises to be an unruly and unpredictable spectacle.

Ken spoke fondly about the video footage which recorded ‘the urgency of “performance” of the people who are responding to the inflatables. Today inflatable making and use is more controlled, in the 60s control was only minimally observed, to prevent injuries. But in all our activities over 10 years of air structure events, we had only one fractured limb.’Young people sliding down the side of an inflatable structure - Action Space archive

Great Bear cameo!

Another great thing about the film is that the Great Bear Studio will have an important cameo role.

Huw came to visit us to shoot footage of the transfers. He explains his reasons:

‘I’d like viewers to see the set up for the capturing of the footage used in the film. Personally it’s very different seeing the reel played on a deck rather than scanning through a quicktime file. You pay a different kind of attention to it. I don’t want to be too nostalgic about a format I have never shot with, yet there seems to be an amateur quality inherent to the portapak which I assume is because the reels could be re-recorded over. Seeing material shot by children is something the super 8mm footage just doesn’t have, it would have been too expensive. Whereas watching children grabbing a portapack camera and running about with it is pretty exciting. Seeing the reels and machines for playing it all brings me closer to the experience of using the actual portapak cameras. Hopefully this will inform the filming and editing process of this film.’

We wish Huw the very best for his work on this project and look forward to seeing the results!

***Big thanks to Ken Turner and Huw Wahl for answering questions for this article.***

Notes

[1] Walter Benjamin, ‘The Task of the Translator,’ Selected Writings: 1913-1926, Volume 1, Harvard University Press, 2006, 253-264, 254.

[2] Action Space Annual Report, 1972, accessed http://www.unfinishedhistories.com/history/companies/action-space/action-space-annual-report-extract/.

D1, D2 & D3 – histories of digital video tape

Monday, July 14th, 2014

D1 tape

The images in this article are of the first digital video tape formats, the D1, D2 and D3. The tendency to continually downsize audiovisual technology is clearly apparent: the gargantuan shell of the D1 gradually shrinks to the D3, which resembles the size of a domestic VHS tape.

Behind every tape (and every tape format) lie interesting stories, and the technological wizardry and international diplomacy that helped shape the roots of our digital audio visual world are worth looking into.

In 1976, when the green shoots of digital audio technology were emerging at industry level, the question of whether Video Tape Recorders (VTRs) could be digitised began to be explored in earnest by R & D departments based at SONY, Ampex and Bosch G.m.b.H. There was considerable scepticism among researchers about whether digital video tape technology could be developed at all because of the wide frequency required to transmit a digital image.

In 1977 however, as reported on the SONY websiteYoshitaka Hashimoto and team began to intensely research digital VTRs and ‘in just a year and a half, a digital image was played back on a VTR.’

Several years of product development followed, shaped, in part, by competing regional preferences. As Jim Slater argues in Modern Television Systems (1991): ‘much of the initial work towards digital standardisation was concerned with trying to find ways of coping with the three very different colour subcarrier frequencies used in NTSC, SECAM and PAL systems, and a lot of time and effort was spent on this’ (114).

Establishing a standard sampling frequency did of course have real financial consequences, it could not be randomly plucked out the air: the higher the sampling frequency, the greater overall bit rate; the greater overall bit rate, the more need for storage space in digital equipment. In 1982, after several years of negotiations, a 13.5 MHz sampling frequency was agreed. European, North American, ‘Japanese, the Russians, and various other broadcasting organisations supported the proposals, and the various parameters were adopted as a world standard, Recommendation 601 [a.k.a. 4:2:2 DTV] standard of the CCIR [Consultative Committee for International Radio, now International Telecommunication Union]’ (Slater, 116).

The 4:4:2 DTV was an international standard that would form the basis of the (almost) exclusively digital media environment we live in today. It was ‘developed in a remarkably short time, considering its pioneering scope, as the worldwide television community recognized the urgent need for a solid basis for the development of an all-digital television production system’, write Stanley Baron and David Wood.

Once agreed upon, product development could proceed. The first digital video tape, the D1, was introduced on the market in 1986. It was an uncompressed component video which used enormous bandwidth for its time: 173 Mbit/sec (bit rate), with maximum recording time of 94 minutes. D-2 and D-3 Tapes

As Slater writes

‘unfortunately these machines are very complex, difficult to manufacture, and therefore very expensive […] they also suffer from the disadvantage that being component machines, requiring luminance and colour-difference signals at input and output, they are difficult to install in a standard studio which has been built to deal with composite PAL signals. Indeed, to make full use of the D1 format the whole studio distribution system must be replaced, at considerable expense’ (125).

Being forced to effectively re-wire whole studios, and the considerable risk involved in doing this because of continual technological change, strikes a chord with the challenges UK broadcast companies face as they finally become ‘tapeless’ in October 2014 as part of the Digital Production Partnership’s AS-11 policy.

Sequels and product development

As the story so often goes, D1 would soon be followed by D2. Those that did make the transition to D1 were probably kicking themselves, and you can only speculate the amount of back injuries sustained getting the machines in the studio (from experience we can tell you they are huge and very heavy!)

It was fairly inevitable a sequel would be developed because even as the D-1 provided uncompromising image quality, it was most certainly an unwieldy format, apparent from its gigantic size and component wiring. In response a composite digital video – the D2 – was developed by Ampex and introduced in 1988.

In this 1988 promotional video, you can see the D-2 in action. Amazingly for our eyes and ears today the D2 is presented as the ideal archival format. Amazing for its physical size (hardly inconspicuous on the storage shelf!) but also because it used composite video signal technology. Composite signals combine on one wire all the component parts which make up a video signal: chrominance (colour, or Red Green, Blue – RGB) and luminance (the brightness or black and white information, including grayscale).

While the composite video signal used lower bandwidth and was more compatible with existing analogue systems used in the broadcast industry of the time, its value as an archival format is questionable. A comparable process for the storage we use today would be to add compression to a file in order to save file space and create access copies. While this is useful in the short term it does risk compromising file authenticity and quality in the long term. The Ampex video is fun to watch however, and you get a real sense of how big the tapes were and the practical impact this would have had on the amount of time it took to produce TV programmes.

Enter the D3

Following the D2 is the D3, which is the final video tape covered in this article (although there were of course the D5 and D9.)

The D3 was introduced by Panasonic in 1991 in order to compete with Ampex’s D2. It has the same sampling rate as the D2 with the main difference being the smaller shell size.

The D3’s biggest claim to fame was that it was the archival digital video tape of choice for the BBC, who migrated their analogue video tape collections to the format in the early 1990s. One can only speculate that the decision to take the archival plunge with the D3 was a calculated risk: it appeared to be a stable-ish technology (it wasn’t a first generation technology and the difference between D2 and D3 is negligible).

The extent of the D3 archive is documented in a white paper published in 2008, D3 Preservation File Format, written by Philip de Nier and Phil Tudor: ‘the BBC Archive has around 315,000 D3 tapes in the archive, which hold around 362,000 programme items. The D3 tape format has become obsolete and in 2007 the D3 Preservation Project was started with the goal to transfer the material from the D3 tapes onto file-based storage.’

Tom Heritage, reporting on the development of the D3 preservation project in 2013/2014, reveals that ‘so far, around 100,000 D3 and 125,000 DigiBeta videotapes have been ingested representing about 15 Petabytes of content (single copy).’

It has then taken six years to migrate less than a third of the BBC’s D3 archive. Given that D3 machines are now obsolete, it is more than questionable whether there are enough D3 head hours left in existence to read all the information back clearly and to an archive standard. The archival headache is compounded by the fact that ‘with a large proportion of the content held on LTO3 data tape [first introduced 2004, now on LTO-6], action will soon be required to migrate this to a new storage technology before these tapes become difficult to read.’ With the much publicised collapse of the BBC’s (DMI) digital media initiative in 2013, you’d have to very strong disposition to work in the BBC’s audio visual archive department.

The roots of the audio visual digital world

The development of digital video tape, and the international standards which accompanied its evolution, is an interesting place to start understanding our current media environment. They are also a great place to begin examining the problems of digital archiving, particularly when file migration has become embedded within organisational data management policy, and data collections are growing exponentially.

While the D1 may look like an alien-techno species from a distant land compared with the modest, immaterial file lists neatly stored on hard drives that we are accustomed to, they are related through the 4:2:2 sample rate which revolutionised high-end digital video production and continues to shape our mediated perceptions.

End of year thank yous to our customers

Monday, December 16th, 2013

What a year it has been in the life of Great Bear 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.

Throughout the year we have been transported to a breathtaking array of places and situations via the ‘mysterious little reddish-brown ribbon.’ Spoken word has featured heavily, with highlights including Brian Pimm-Smith‘s recordings of his drive across the Sahara desert, Pilot Officer Edwin Aldridge ‘Finn’ Haddock’s memories of World-War Two, and poet Paul Roche reading his translation of Sophocles’ Antigone.

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.

Rack of three digital multi-track machines 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.

Transfer Digital Betacam (DigiBeta) to Quicktime or AVI now, one day they will be obsolete

Monday, November 4th, 2013

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.

Digibeta_close up right angle

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 digi-beta is designed to counter such damage because it allows you to replace the filters around the head drum area should they become clogged.

dvw-a510-digital-betacam-loading-gear

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 digi-beta 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!

So send us your digi-beta tapes!

D1 digital video transfer – new additions and economies of size

Monday, June 10th, 2013

A recent addition to the greatear digitising studio is a BTS D1 digital video cassette recorder.

As revolutionary as it was at the time, early digital audio and video tape recording is more threatened with obsolescence than earlier analogue formats.

bts-dcr-300-d1-digital-video-recorder

Introduced in 1986, D-1 was the very first, real-time, digital broadcast-quality tape format. It stored uncompressed digitized component video, had uncompromising picture quality and used enormous bandwidth for its time. The maximum record time on a D-1 tape is 94 minutes.

Enormous is certainly the word for the D1 tape! Compared with the so-called ‘invisible’ nature of today’s digital data and the miniDV introduced in 1998, this tape from 1992 is in comedy proportions.

d1-minidv-tape-comparison-2

D-1 was notoriously expensive and the equipment required large infrastructure changes in facilities which upgraded to this digital recording format.

Early D-1 operations were plagued with difficulties, though the format quickly stabilized and is still renowned for its superb standard definition image quality, sometimes referred to as a ‘no compromise’ format.

D-1 kept the data recorded as uncompressed 8bit 4:2:2, unlike today where compression is required for digital data to save space and time for practical delivery to the home, but sacrificing the picture and sound quality in the process.

D1 was supplanted by subsequent D models that recorded a combination of component (D5) and composite (D3) signals.


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