[BC] Fun with Quad Videotape

[Xen Scott]

At 07:57 AM 12/03/2011 -0500, Ton Taggart wrote:
>Rowan & Martin edited using mechanical splices in 1970??
>
>Very strange.  In 1970, I was using an Editec on an Ampex
>quad machine (1200 series) at Channel 8, Cleveland. The
>Editec "knew" to do the inserts at the particular frame
>points where it would not be noted. Find your edit point,
>mark with a cue tone on the cue channel, back up the source
>machine, and the Editec machine 5 seconds (there were
>mechanical footage timers on the machines) and hit play on
>both. As I recall, there was a rehearsal mode so you could
>see exactly where your edit point was, and then adjust the
>point a second or two backwards or forwards.

I used an Editec equipped Ampex VR-1000C back in 1965 to do
electronic editing.  I also did physical splicing of quad tape
when electronic editing was not available or the edit didn't need
to be frame accurate.  I still have an empty can of Edivue.

One of the many challenges of physical editing of quad tape is that
the audio track is offset from the video by 19 frames or about
10 inches on a tape recorded at 15ips.  Then there's the momentary
change in the thickness of the tape caused by the splicing tape.
That would change the video head penetration and consequently
produce a big momentary time-base error.

I would be surprised if Rowan & Martin was constructed with much,
if any, physical editing.  Physical edits have too many limitations to
have been practical for a show like that.

By the early 1970's, electronic editing had begun to use a time-code
signal recorded on a secondary audio track (cue track) to control
the electronic edit.  By this time, many editing systems controlled
both the edit machine and the source machine(s).  This made electronic
edits with frame accurate precision and provided a preview mode so
adjustments could be made.  By then, the slowest part of the editing
process was the decision making by the producer/client.

Xen Scott
Videotape Editor
The Mike Douglas Show
and other Group W programs
1968-1982