by Patrick Feaster, Media Preservation Specialist, Media Digitization and Preservation Initiative, Indiana University
MDPI has a ravenous appetite. To keep all its lines running at capacity, it needs to be fed around three thousand media objects per week. The stalwart band of workers responsible for dishing up the necessary diet of tapes and discs is known as the Strategic Media Access Resource Team—the “SMARTeam” for short. And when it comes to wrangling masses of outmoded media, there’s nobody smarter. These folks know their VHS from their U-matic, their Type I audiocassette from their Type IV, their microgroove from their coarse. They’re savvy about speeds and track configurations and sound fields, and they could rattle off the product numbers of sticky-shed tape stocks in their sleep.
However, they rely almost entirely on visual inspection. They look closely at each object as they prepare it, maybe going so far as to hold it up to the light to check for translucence, and they also study whatever’s printed or written on it. But with rare exceptions—limited to CD-Rs and DATs—they never actually put anything into a machine.
Usually this works out just fine, but not always. After all, some formats are masters of disguise!
Consider Betamax, a consumer videocassette system introduced in 1975 and remembered today mostly for having lost the videotape format war to the rival VHS format. Last August, we delivered a batch of tapes to Indiana University Media Digitization Studios (IUMDS) for reformatting that looked all the world like Betamax. They displayed the distinctive Betamax logo, the cassettes had the expected design, and the curatorial unit they’d come from had identified them as Betamax.
But when these tapes reached MDPI video preservation engineer Rob Mobley, we were in for a surprise. The recordings on the tapes weren’t Betamax, he told us, but Betacam—a higher-resolution format intended for broadcast and professional use.
When Sony had launched the first Betacam system in 1982, it had offered a new line of cassettes manufactured especially for it. These tapes are clearly labeled and easily recognizable; the SMARTeam knows them well as “Betacam Oxide.” However, it turns out that some users had substituted Betamax cassettes in their Betacam recorders. Sony discouraged the practice—the newer cassettes had been designed more robustly to support the higher tape speed of Betacam—but it was possible because both cassette types used the same ferric oxide tape in a shell of the same basic structure. Of course, a Betamax tape with a Betacam recording on it looks exactly like a Betamax tape with a Betamax recording on it. There’s no way to tell the two apart through visual inspection.
In effect, we’d been fooled by a bunch of Betacam tapes cunningly disguised as Betamax. Since the MDPI workflow for Betacam is entirely different from the MDPI workflow for Betamax, this meant everything had to be re-prepared.
And our Betamax woes didn’t end there.
This February, we delivered some more Betamax cassettes to IUMDS from the Indiana Fiddlers’ Gathering collection at the Archives of Traditional Music. But what turned out to be on them sure didn’t look much like a fiddlers’ gathering. Instead, it looked like this:
What we’re looking at here isn’t video at all, but audio. In 1981, Sony had introduced a digital audio processor called the PCM-F1. Priced at $1900—a fraction of the cost of earlier PCM adaptors—it was the first widely affordable processor for digital audio recording. But it had no built-in recording mechanism of its own. Instead, it had to be connected to a separate videotape recorder, the only kind of recording device available at the time that could handle the serious bandwidths involved. Digital audio data coming out of the PCM-F1 would be recorded as a video signal made up of monochrome dots and bars, and this video signal could then be played back through the PCM-F1 and reconverted into audio. Any kind of videotape was theoretically fair game, but in practice Sony PCM-F1 machines were most often paired with Sony Betamax decks. This cumbersome arrangement was superseded by the more familiar DAT format in 1987.
We’d known from our Media Preservation Survey that there were PCM-F1 recordings on Betamax cassettes at the Music Library and in the Recording Arts program. But a Betamax tape with a PCM-F1 recording on it looks exactly like a Betamax tape with a Betamax recording on it, so with the Indiana Fiddlers’ Gathering tapes we’d been fooled yet again.
You can’t judge a Betamax cassette by its cover.
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