[QuadList] Electronic Editing Notes

[dcfwtx at aol.com]

Chris,


In my experience with a tape facility with RCA and Ampex edit devises, the RCA TR 70's made a more predictable edit in insert from a stability standpoint than the VR 2000. They both thad their routines and procedures for setup, and your success with the edit was generally seen by the bounce of the Colortec/Amtec/stab dots. The RCA seemed to always be a lot easier to get a real nice looking edit. Color framing also seemed more predictable on the TR 70's. 


Burbank had a CMX 300 tied to four VR2000's (very early production runs). For those not familiar with the 300, it was a punch tape EDL. Off lines were done on an ISC system. I do not recall the computer that drove the CMX. One producer (now a family friend) told me that on one occasion, editor Bob Veatch had to build an entire show or promo backwards (from end of show to the top) due to a problem with the VR 2000 record deck (poor insert edits that came in too early). But, he got the job done. Just another day in the network trenches.


David Crosthwait
DC Video
www.dcvideo.com





-----Original Message-----
From: Chill315 at aol.com
To: quadlist at quadvideotapegroup.com
Sent: Fri, Jan 29, 2010 6:07 am
Subject: [QuadList] Electronic Editing Notes


We all have had our share of the trials and tribulations of editing.  I started doing the cutting of the tapes and ended using PCs and data with no tape.  The stories are wide spread.
 
I did some thinking about how did we get to the Electronic Editor.  Splicer for the RCA folks.
 
As far as I know the first machine that you could edit on was the VR-1000.  There was a 2 or 3 rack unit chassis that was installed with square buttons on the front.
 
To get to this required a lot of changes.  First was the development of the Intersync to get the machine to frame vertically and lock horizontally to the incoming video.  Second was the change to the master erase head.  It had to be split so that it only erased the Video tracks and the control track in full record.  That had to be an interesting challenge as the strength of the erase field could not lap over into the cue or audio track and cause any erasure there.  Third was the sequencing of the control so that the turn on times would be correct.  It had to be exact for the edit to occur at the correct point.
 
I was thinking about AMPEX and the changes to the erase stack over the years.  First they had a front of tape full erase.  Then they went to a moveable head.  That must have been a variable in terms of trying to get the erase delay perfect every time.  Finally there was the back of tape erase assembly.  Interesting the position with respect to the video record head was shortened with the last head.  Thus the delay was changed by a few frames.  Note that the canoe was not changed and thus still met SMPTE specs.  The erase assembly had to have a cue track head added so that the EDITEC could read the cue tone early enough to do the edit.  
 
I never heard about RCA having an electronic splicer before the TR-22.  I do think that they had an innovative way to check the timing of the splice and set the capstan speed.  Much better than AMPEX in my opinion.  If RCA had only the equivalent of an EDITEC in the early days.  AMPEX did copy the splice timing procedure in the AVR-2.  
 
I was thinking about some of the stories that I went through as I was reading the posts.  I was glad that the only 7.5 IPS recordings that I did were not edited.  Just think of the wait time of 30 or 36 frames from push of button to start of edit.
 
I still remember the chief engineer of an unnamed place now out of business that did a recording on 3/4 tape in the insert mode to edit as he went along.  The tape was blank and thus no control track.  We were able to salvage it by building a control track in another machine jumpering circuits from one machine to another while the tape was playing and doing some return jumpers.  The recording was the president of a top 10 corporation giving an important address that could not be repeated.  Did we save their bacon on that one.
 
Late at night I once hit record on the wrong machine and wiped a bit of a master.  Fortunately we could reconstruct it very quickly.  Those all nighters were terrible.
 
I even sliced a dub at the wrong spot late at night.
 
We had editors that would hit the buttons on the RA-400 with a lot of force and actually sent them through the bottom a few times.  Fortunately I had spares after the first time.  I was able to steal an unused one the first time and had enough the rest of the times.
 
Assemble vs Insert was not an issue with us.  We only did insert and the machines other than for a couple of months were under a controller.  Either an AMPEX RA-4000 or a CMX control.  Thus the need for insert.  It was interesting that all edits were Video only inserts in the structure of the CMX.  The audio was run as an separate insert that controlled.  Thus the split edit capability.  The RA-4000 did not have that feature but it was not that big a deal to us.  We did CMX editing with AVR-2's and RA-4000 with VR-1200 and AVR-2's.
 
The 1200 audio chassis did the audio editing.  It was hard to get a really good clean no thump edit.  The audio turn on times were the key.  Still it was never perfect.  The AVR-2 had better timing circuits but CMX built their own piggy back board.  Who know why.
 
I do remember that he RA-4000 would let us start the show exactly at zero time code.  The CMX could not handle the transition through zero.  To see the machines go crazy when we got our first CMX was nuts.  You had to stop it fast.  The RA-4000 was a great edit controller but it did not have any memory.  Paper was our savior.  Yet I could out pace a CMX most days on 30 sec drop in the product spots.  
 
That is just some of the things that come to mind.  I hope that we all look back and thank our lucky stars for being able to see the great leaps that were made.
 
Chris Hill
WA8IGN
 
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