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     Video Art / Media Art Preservation:  Studies and Suggestions
                     THE DANISH VIDEO ART DATA BANK

Emulation as a preservation strategy

NB: This text should be supplemented with more specialised information about emulation-srategies!

The days of the video tapes are numbered. The evolution is going quicker and quicker. Go to any supermarket selling “videos” and it is becoming more and more difficult to find the film you want on video. They are all on DVD today.

 Many artists already skip the “old-fashioned” tape technique – especially if they want to create interactive media art installations and/or web-based or web-independent works but also with “straight-forward” works.
Video and media art in the future will be stored not on magnetic tape but on digital discs so we should already now face the problem: how to preserve this digital information for the future?  

The problem is stated very clearly by Jeff Rosenberg when he points out that “There is a yet no viable long-term strategy to ensure that digital information is readable in the future” and go on to say that “Digital documents are vulnerable to loss via decay and obsolescence of the media on which they are stored, and they become inaccessible and unreadable when the software needed to interpret them, or the hardware on which that software runs, becomes obsolete and is lost.” (1) 

We have already touched upon the obsolescence problem with video/media art on magnetic tapes. The problem is a double problem: First because different types of the magnetic tapes are becoming or are already obsolescence – take for example many of the old open real tapes or cassette tapes like Philips 2000 and now it is said that Sony will stop manufacturing U-matic tapes. Second because also the hardware to run the tapes on, the tape machines and the monitors, are becoming or are already obsolescence because they are not manufactured any more and the know-how and spare parts to repair them are disappearing.  Third because computers used in may video installation to program the “behaviour” of the installation may become obsolete  not only regarding the software program used but also the type of computer itself. This is  - as accounted for in the American-Canadian book reviewed above (2) - already a problem with The Erl King, an interactive video installation by Grahame Weinbren and Roberta Friedman from 1982-85, using Pascal MT+ program with the minimal CP/M operating system on a primitive Zilog Z-80 personal computer with a touch screen and a custom-built interface to multiple laser discs.

Most often the works on the old tapes have been “preserved” by migration: copying them onto newer type of tapes (for example from open reel tapes to U-matic and from U-matic to Betacam) but it could be – and has been – argued that migration do somehow make it possible to still see the work but it is not a real preservation of the original because in the copying process you have inherent a loss to some degree of the original information – for every time you copy you start a decay process. Migration can’t preserve the original. Migration can provide future access to the art work but not to the original.
With the digital stored information you don’t have the same problem: a copy, we are told, is exactly  the same as the original – so you might say that you don’t have an original and a copy but two originals!?
But this is a truth with modifications! It is only true if you copy the digital stored information on the same hardware platform and with the same original application software as the original and in a way so the bit stream is not changed, corrupted by compression inadvertent transformation, imperfect copying with bit loss, etc.  

The emulation technique has been suggested as a way to solve this. Emulation as a preservation strategy has mainly been discussed in connection with preserving digital texts and still making them readable when facing the problems in the future of obsolete software (and also obsolete hardware).

In the passage about the “Guggenheim initiative” we referred to “emulation” in relation to “migration” and reinterpretation” (3):

* To emulate an artwork is to devise a way of “imitating” the original look by completely different means (“imitating” an analogue video work on digital video or DVD and so on). This could however be inconsistent with the artist’s intent.

* To migrate an artwork involves upgrading equipment and source material. The analogue LB Umatic videotape and player could be upgraded to an analogue HG Umatic or Betacam tape/player. The major disadvantage of migration is that the original appearances of the artwork will probably change on its new medium – see the discussion (raised by Montevideo) about the moral question.

* The most radical preservation strategy is to reinterpret the work each time it is re-created. This would mean to ask what contemporary medium would have the metaphoric value of the original medium. This would not always be possible and it is a dangerous technique when not warranted by the artist.

Although emulation as a preservation strategy in the first instant has been used when the preservation problems involved computers it can of course be used to the substitution or refabrication of the components of any artwork. It will in the future when video is totally an digital technique and if you preserve the old analogue video tapes to digital carriers also be an important strategy concerning preservation of video art.
You could talk about hardware-for hardware emulation if you substitute or refabricate the equipment or material of an artwork, about software-for-software emulation when a program emulates another kind of software, and about software-for-hardware emulation when new software impersonates old hardware and you simulate a program’s original hardware environment on a machine that it was not intended to run it.

NB: For a more thorough, detailed and specialised treatment of emulation-strategy see some of the texts mentioned in the notes and referencies in these texts!
You can findt a meticulous explanation of emulation as a preservation technique you should go to texts by Jeff Rosenberg (4) (5). If you prefer – first – to get “emulation in a nutshell” then go to a text by David Holdsworth and Paul Wheatley (6).

Torben Soeborg



(1) From “Executive summary” in Jeff Rosenberg: Avoiding Technological Quicksand: Finding a viable Technical Foundation for digital Preservation, CLIR, January 1998,  

(2) Jeff Rothenberg: “Grahame Weinbren and Roberta Friedman, The Erl King, 1982-85, p. 100-107, in: Alain Depocas, Jon Ippolito & Caitlin Jones (edit): Permanence Through Change: The Variable Media Approach / La permanence par le changement: L'approche des médias variables, Guggenheim Museum Publications, NY, USA & La fondation Daniel Langlois pour l'art, la science et la technologie, Montreal, Canada, 2003, ISBN 0-99684693-2-9

(3) VIDEO ART\e-monitor No. 5: 

(4) Jeff Rosenberg: Avoiding Technological Quicksand: Finding a viable Technical Foundation for digital Preservation, CLIR, January 1998,
(5) Jeff Rosenberg: Digital Information Lasts Forever – Or Five Years, Whichever Comes First, October 2001,

(6) David Holdsworth and Paul Wheatley: Emulation, Preservation and Abstraction, CAMiLEON Project, University of Leeds, without date,