This where I disagree with referencing to input video for the SRW 5500 and similar decks. When I'm outputting to these decks if the Avid burps it sends an unstable signal to the record deck before the record off strobe has gotten to the deck. You can hear the results if you are near the machine. The drum servo will do it's best to resync to the unstable signal. This puts a for all intents and purposes permanent glitch at that point in the tape. It is very much like a hard record punch in, although that may not what is actually happening it acts like the punch out of an asssemble edit. There is no way to remove this glitch except for making an assemble edit to the end of the tape. As I've already mentioned earlier in this thread this is a very bad thing, especially when you are trying to punch in a fix in the middle of a master.
Through trial and error I have found that if I set the SR deck to external reference when the avid burps the deck doesn't try to resync to the unstable signal and therefore doesn't make the permanent glitch. This method is not full proof but it certainly has reduced this problem for me. So because of this behavior of SR decks and perhaps HDCam decks I always use external reference whenever possible.
--- In Avid-L2@yahoogroups.com, Dennis Degan <DennyD1@...> wrote:
>
>
> It was previously stated:
>
> > "Virtually every "VTR Tech" I meet from rental houses always suggests using video input servo reference"
>
> On Nov 12, 2013, at 7:14 PM, Mark Spano wrote:
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> > This is because virtually every "VTR Tech" from those places is tired of hearing calls about "why is the stop light flashing" and "how do I adjust vertical hold on my layoff". This 'advice' is only for people who rent decks and have little to zero knowledge of how they should be used. My advice is to ask me, or ask Bob Z, who would (I am sure) tell them what I'm telling you. And we both have loads of experience trying to scrub the world of nonsense advice being passed off as sound…
>
> I jump in:
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> One of the reasons a reference switch is present on the machine is because there are many ways these VTR's can be installed and used. I have always told users to set the servo reference to 'auto' because when you are recording video, you WANT the servo to follow the input video. When you are playing back, you WANT the servo to lock to the external reference. 'Auto' allows both conditions to happen. If the machine records input video using a different external reference, there is the possibility that the recording will be no good because there is no guarantee that the reference matches the input video. Your advice, as well-meaning as it may be, could result in a totally useless recording, and you would not know it until you tried to play it back later. I'm sure that the reference at your facility is coincident with all your edit rooms' video outputs, so for you it's not an issue.
> I've known Bob Zelin for 33 years. I think it's a bit presumptuous to assume he would offer your advice. Your reasoning for why "VTR Techs" would give this advice is inaccurate. Perhaps your reasoning is derived from your own experience, but it's wrong information. The fact is, when recording input video on a VTR, it is ALWAYS best to use that input video as the reference. If you have bad input video causing trouble, using an external reference for recording is NOT the way to fix it.
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> Dennis Degan, Video Editor-Consultant-Knowledge Bank
> NBC Today Show, New York
>
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