Three Decades of Video
On a snowy morning just under 35 years ago, I received a
call telling me that my long-awaited first piece of video equipment was ready to be picked
up. Fortunately, cars in the mid-1960s were a lot bigger than they are today because I
arrived to find a couple of brawny fellows manhandling a crate the size of a refrigerator
toward my car. The box contained a video recorder: 100 pounds of cast iron, walnut, and
various fragile bits of electronics and mechanics.
In those days, home video had something of the flavor of
science fiction. Even professional video recorders had only been around a bit more than a
decade, and they were still huge and expensive; most TV stations could only afford one, if
they had tape equipment at all. The idea that ordinary consumers would be able to get into
the act anytime soon seemed like a fantasy.
Nevertheless, there were lots of attempts to tame the
television signal. Electronics magazines of the day were full of peculiar schemes to
preserve video for a reasonable cost. I recall one mysterious bit of technology called
"thermoplastic recording" that apparently melted the picture into the surface of
a moving film; it could either be played back electronically or projected on a screen, and
erasure was a matter simply of re-melting the surface. Oddly enough, the technique went
nowhere.
In spite of such imaginative solutions, most of the
electronics industry agreed that some form of magnetic videotape was necessary. The
difficulty was that audio recorders of the day could just barely manage to respond to a
full audio signal; a TV picture required 300 times the audio bandwidth!
Gradually, a system of "helical scanning"
matured. Recording a series of video tracks side by side diagonally across the tape had
been done in professional machines, and it seemed likely that the technique would
ultimately be adapted for home use. It was, but the final form took another decade to
appear. In the meantime, there were numerous hopeful but abortive attempts, my walnut
behemoth being only one example.
Today, it's easy to be blasé about home video because all
that effort to develop a workable system did ultimately pay off. In everything but the
details, that old recorder crammed into the back of my Pontiac worked the same way as
today's most sophisticated machines, but it was those details that turned the system into
a workable consumer product.
For one thing, the video recorders of the sixties were
open-reel, and even harder to thread than their audio counterparts. Rather than simply
pulling the tape from one reel to another past the heads, you had to wrap it manually
around a metal drum about six inches in diameter, and then feed it to the takeup reel.
People tended to balk at open-reel audio recorders; there was no way they would put up
with this awkwardness. Only when the professional U-matic system adopted a workable
mechanism to pull the tape out of a cassette and wrap it automatically around the head
drum did video become practical for ordinary users.
Then there was the amount of tape necessary. My early
recorder used one-inch tape traveling at 9.6 inches per second, which meant that a
ten-inch reel of tape held one hour of material. The cost, in 1966 funds, was a crushing
$90 a reel, so in the years I used that machine I used the tape that came with it and
never bought another.
To reduce this burden, a number of techniques had to be
developed. First was to use two heads mounted on opposite sides of the drum, each
responsible for half the picture. Tape with higher particle density assisted in reducing
linear tape speed as well; the first of these, chromium dioxide, was developed primarily
for video applications, although in the event it was used more commonly for audio.
Finally, the developers of the first successful consumer
system -- Sony's Betamax -- intentionally compromised picture quality. By bringing
everything down to the minimum acceptable quality, it was possible to produce both
recorders and cassettes that were affordable. The definition of affordable has changed
somewhat since that time, of course: then it meant a $1,000 machine and a $25 tape.
The scramble to make consumer video a reality between about
1965 and 1975 was so frenzied that there was little doubt some workable system would
emerge. That it took a further decade or so for the video companies to rework their
systems to undo the technical compromises that had made the first systems possible does
not seem all that unreasonable now, although it seemed to take forever at the time. The
irony is that, even now almost no one owns an improved Super VHS recorder and there are
virtually no commercial tapes available. Still, Super VHS, the Hi8 camcorder system and
the DVD at least make broadcast-quality video available to anyone.
After more than three decades of dabbling in video I still
have my walnut wonder, although it now serves as furniture rather than equipment. It also
serves as a reminder of how far we've come.
...Ian G. Masters
ian@mastersonaudio.com
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