First, there was preservation by benign neglect: put your cultural artifacts in a cold, stable environment and leave them alone until they are needed. Then came certain artifacts that required a mediating technology, and things started to get a bit more complicated.
The New York Times article “The Afterlife Is Expensive for Digital Movies” draws attention to a report, “The Digital Dilemma,” which attempts to quantify the incredible costs of maintaining movies in digital form.
What we know:
To begin with, the hardware and storage media—magnetic tapes, disks, whatever—on which a film is encoded are much less enduring than good old film. If not operated occasionally, a hard drive will freeze up in as little as two years. Similarly, DVDs tend to degrade: according to the report, only half of a collection of disks can be expected to last for 15 years, not a reassuring prospect to those who think about centuries. Digital audiotape, it was discovered, tends to hit a “brick wall” when it degrades. While conventional tape becomes scratchy, the digital variety becomes unreadable.
Difficulties of that sort are compounded by constant change in technology. As one generation of digital magic replaces the next, archived materials must be repeatedly “migrated” to the new format, or risk becoming unreadable.
What we don’t know: what to do for the long-term preservation of digital objects. So, short-term strategies are pursued, such as storing born-digital movies in film format (which, unfortunately, yields images of lower quality than those obtained through a pure film process).
Also discussed in this article is the added problem of the proliferation of material in digital form: “digital production … sometimes generates more storable material.” This raises the need for appraisal.
Link to “The Afterlife Is Expensive for Digital Movies”: http://www.nytimes.com/2007/12/23/business/media/23steal.html