Writing in The Atlantic, Craig Saper extols the virtues of microfilm for, among other things, its potential to last for up to 500 years.
Their [microfilm rolls] longevity was another matter. As early as May 17, 1964, as reported in The New York Times, microfilm appeared to degrade, with “microfilm rashes” consisting of “small spots tinged with red, orange or yellow” appearing on the surface. An anonymous executive in the microfilm market was quoted as saying they had “found no trace of measles in our film but saw it in the film of others and they reported the same thing about us.” The acetate in the film stock was decaying after decades of use and improper storage, and the decay also created a vinegar smell—librarians and researchers sometimes joked about salad being made in the periodical rooms. The problem was solved by the early 1990s, when Kodak introduced polyester-based microfilm, which promised to resist decay for at least 500 years.
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There’s a reason for that: Those keys and knobs are still in use. Microfilm machines haven’t been mined for their decontextualized parts, and they are not yet truly obsolete. The devices are still in widespread use, and their mechanical simplicity could help them last longer than any of the current electronic technologies. As the web comic xkcd once observed, microfilm has better lasting power than websites, which often vanish, or CD-roms, for which most computers don’t have readers anymore.
The xkcd comic gets a laugh because it seems absurd to suggest microfilm as the most reliable way to store archives, even though it will remain reliable for 500 years. Its lasting power keeps it a mainstay in research libraries and archives. But as recent cutting-edge technologies approach ever more rapid obsolescence, past (and passed-over) technologies such as the microfilm machine won’t go away. They’ll remain, steadily doing the same work they have done for the past century for another five more at least—provided the libraries they are stored in stay open, and the humans that would read and interpret their contents survive.
In fact, the National Archives continues to use microfilm precisely because of these features.
In an era of digitization, NARA continues to microfilm records because microfilm is a low-cost, reliable, long-term, standardized image storage medium. The equipment needed to view microfilm images is simple, consisting of light and magnification. The medium has a life-expectancy of hundreds of years.
Much of the rest of Saper’s article, however, is devoted to praising microfilm for being unwieldy and difficult to use. You might have to spend an inordinate amount of time locating a specific article on a microfilm, for example, but at least Google isn’t recording and selling your specific search.