As I said I do this out of habit and it's not just bad wiring that causes things to be out of the record machines acceptable window. I've had a situation where a Sony 5500 and 5800 side by side set up identically were fed the same FCP 7 output from a Kona 3. One deck accepted it with deck set to external reference and the other didn't. I found that if I adjusted the video output timing on the Kona control panel and then both decks would accept the signal without issue. In this case switching the record machine to servo reference input video also solved the problem but I was stubborn and wanted to lock everything to external reference so I found the timing adjustment. That's a setting that virtually no one uses because what the F is timing these days.
I'll just agree to disagree on the nomenclature of what reference input video should mean and do. To me it should mean the video signal that is being sent to the record heads whether it comes from the back spigot or the internal generator it should lock to the incoming video source to the record circuitry. The internal generator should lock to an external sync reference if one is present. I have no idea why the internal generator on the 5500 seems to be way out of time with a normal EtoE signal through the deck but that's been my observation when watching the decks downconvert feed a beta sp deck that was externally referenced. I've been told by many on this list that they always run with decks servo reference to input video to avoid the myriad of problems I've mentioned. I've always done the digital cuts the way you suggest to avoid punching a hole in the SR tape, figuratively not literally. Virtually every "VTR Tech" I meet from rental houses always suggests using video input servo reference so there appears to be some misinformation out there. I'll stick with external for all my digital cuts. Give me sync or give me .....
--- In Avid-L2@yahoogroups.com, Mark Spano <cutandcover@...> wrote:
>
> You say:
>
> "I never ever ever feed video input to a deck when blacking because
> contrary to what you say it does have an effect on the servo reference if
> you are set to video input."
>
> That is absolutely true and I never said that. If the servo reference is
> set to Input (which I *never* do), then all bets are off. The servo ref
> looks at Video input and derives servo clock from that. Why ever do that
> when you have an external reference signal that feeds everything in house?
> Leave it set to External and forget it forever. No problems, ever.
>
> also:
>
> "The video startup glitches that are then feed to the deck will cause a
> servo rereference that you can hear at the machine while the drum servo
> tries to relock"
>
> Yes, this will happen if your servo is set to Input. Don't do that. It
> makes sense only if you have NO external reference to provide to both
> machine and Avid. You clearly have this, because you said:
>
> "When digital cutting I lock the avid to reference and I lock the deck to
> external reference and everything is fine."
>
> So External ref for the deck should be it. You won't have any glitches,
> ever, whether striping or laying back.
>
>
> oh wait, you said:
>
> "over the years I've seen many a time when locking the record machine to
> external and not incoming video can create issues if the timing of the
> decks input signal is out of it's window of acceptance."
>
> This can be true if the External reference signals you're providing the
> machine and Avid are DIFFERENT. That's bad wiring and bad design, and I
> don't think you have this problem.
>
>
> another:
>
> "What is illogical is that if I set the deck to lock to input video and I
> set the machine to internal black the servo reference should be derived
> from the internal black signal and not what's being fed to the video input
> connector on the back of the machine. In this case the servo is not
> referencing the actual video signal and that's where problems crop up."
>
> This is not what is happening in real life. The machine is quite literal.
> If you set the Servo ref to Input Video, it looks at that physical input.
> Period. Any signals the machine outputs (either off tape or from its own
> generators) are based on this setting, not the other way around. So if you
> set Servo Ref to Input Video and have no video present at that physical
> input, it has no idea what to use as a clock source for its internal
> generators. If you set Servo Ref to External and supply the deck with your
> SD reference blackburst, the internal generators will clock to that.
>
>
>
>
>
> On Tue, Nov 12, 2013 at 6:09 PM, johnrobmoore <bigfish@...> wrote:
>
> >
> >
> > I found the problem. This was a new vtr position that had not been used
> > before for an HD deck and the HD output of the deck is normaled to the HD
> > deck input so it needed to be dead patched to avoid a feed back loop. I
> > never ever ever feed video input to a deck when blacking because contrary
> > to what you say it does have an effect on the servo reference if you are
> > set to video input. The common issue I've encountered is your deck is being
> > feed from the avid bay. I go to black a tape on the deck with it still feed
> > the Avid output. I set the deck, be it digibeta or SRW 5500 and other Sony
> > decks, to internal black generator. I start blacking and then I go back and
> > quit out of Avid and open another project. The video startup glitches that
> > are then feed to the deck will cause a servo rereference that you can hear
> > at the machine while the drum servo tries to relock. I agree that if I'm
> > set to external servo reference this might not happen but over the years
> > I've seen many a time when locking the record machine to external and not
> > incoming video can create issues if the timing of the decks input signal is
> > out of it's window of acceptance.
> >
> > When digital cutting I lock the avid to reference and I lock the deck to
> > external reference and everything is fine. It's the fact that the SRW 5500
> > internal video generator seems to be vastly out of time with the rest of
> > the world that I opted to use video reference for the servo when blacking
> > internally. What is illogical is that if I set the deck to lock to input
> > video and I set the machine to internal black the servo reference should be
> > derived from the internal black signal and not what's being fed to the
> > video input connector on the back of the machine. In this case the servo is
> > not referencing the actual video signal and that's where problems crop up.
> > It's from years of 3/4 inch maintenance that I'm sensitive to Record Lock
> > Phase type issues and that's what I'm trying to avoid here. I could be I'm
> > just being overly cautious but it's been working a long time for me.
> >
> >
> > --- In Avid-L2@yahoogroups.com, Mark Spano <cutandcover@> wrote:
> > >
> > > You say:
> > >
> > > "To be safe when blacking tapes I unpatch any video input and I switch
> > the
> > > servo reference to input video."
> > >
> > > to me, that means you are disconnecting ref. Don't do that, and your stop
> > > light won't flash. Leave it on External SD Ref and you're good.
> > >
> > > Patching and unpatching video inputs while the deck is set to Internal
> > > Video Signal Gen BLACK has no effect - and will not glitch at all.
> > >
> > >
> > > On Tue, Nov 12, 2013 at 5:32 PM, johnrobmoore <bigfish@> wrote:
> > >
> > > >
> > > >
> > > > I do not disconnect Reference I disconnect the HDSDI video input. I've
> > > > found with Sony decks that even if you are set to internal video signal
> > > > generator if there is a glitch on the video input the deck burps. It
> > > > doesn't make sense but that's how they work. Because of this I always
> > > > unpatch any video input to the deck before blacking.
> > > >
> > > > Another thing I notice is the output of the deck changes drastically in
> > > > timing between normal input/EtoE mode and when set to internal signal
> > > > generator. Also when I switch to internal signal generator the stop
> > light
> > > > starts flashing like there is some sort of reference issue. Because of
> > this
> > > > I got in the habit of always setting the machine to servo reference the
> > > > video input when blacking tapes.
> > > >
> > > > I just got of the phone with Sony and I'm going to try a first
> > birthday to
> > > > see if that alters the behavior. I'm not sure this is a problem but the
> > > > Sony tech confirmed you can black a tape with the machine connected to
> > > > nothing. In that stand alone mode if I am monitoring the composite
> > > > character output I wouldn't expect the character box to sway left and
> > right
> > > > in the picture which is what I'm seeing now. I'm sure I'd have noticed
> > this
> > > > before if it always behaved this way.
> > > >
> > > >
> > > > --- In Avid-L2@yahoogroups.com, Mark Spano <cutandcover@> wrote:
> > > > >
> > > > > Q: why disconnect SD ref when blacking tapes? Seems unnecessary. The
> > ref
> > > > is
> > > > > for servo - if you have no reference, then servo just runs off AC
> > mains,
> > > > > with all its potential irregularities. When blacking tapes, leave SD
> > ref
> > > > > connected, set servo ref to external, and set internal video / audio
> > > > signal
> > > > > generators to black / silence.
> > > > >
> > > > >
> > > > > On Tue, Nov 12, 2013 at 4:50 PM, John Moore <bigfish@> wrote:
> > > > >
> > > > > >
> > > > > >
> > > > > > Got a rental SRW-5500 in today and I've set it up as I always do.
> > > > > > Starting with the Factory vtr settings and tweaking a few thing I
> > > > like. I
> > > > > > run with external sync from composite SD black when doing digital
> > cuts
> > > > to
> > > > > > tape and it works fine. To black the tape I set the deck to black
> > on
> > > > the
> > > > > > internal signal generator and silence for audio. Whenever I black
> > tapes
> > > > > > using the internal generator I always notice the stop light
> > flashes as
> > > > if
> > > > > > there was no sync or problem sync. To be safe when blacking tapes I
> > > > > > unpatch any video input and I switch the servo reference to input
> > > > video.
> > > > > > On today's machine when I looked at the composite character
> > generator
> > > > out
> > > > > > while blacking I noticed the black box of time code was dithering
> > left
> > > > and
> > > > > > right consistantly and then I noticed the front panel of the deck
> > said
> > > > lost
> > > > > > lock. I busted the record and have found that unless I set the
> > servo
> > > > > > reference to auto or external when blacking internally there
> > appears
> > > > to be
> > > > > > some sort of unstable reference like issue. I have never seen this
> > > > > > behavior before and I've worked with this model a lot. You can
> > black a
> > > > > > tape with the machine standalone with no signals using the internal
> > > > > > generators so why is this machine unstable when not set to
> > reference
> > > > the
> > > > > > external sync source? This seems like a broke. Given I reset to
> > > > factory I
> > > > > > feel the main settings are correct. Perhaps there is some odd
> > Novram
> > > > > > setting that is tweaked that I've never had to deal with. I do
> > realize
> > > > > > that for some reason the internal video signal generator always
> > seems
> > > > to
> > > > > > have a very different timing window compared to when the deck is
> > just
> > > > > > inputting a regular HDSDI source but I never seen this instability
> > on
> > > > the
> > > > > > composite output when blacking tapes. Anybody got an idea what
> > might
> > > > be up
> > > > > > here?
> > > > > >
> > > > > > John Moore
> > > > > > Barking Trout Productions
> > > > > > Studio City, CA
> > > > > > bigfish@
> > > > > >
> > > > > >
> > > > > >
> > > > >
> > > >
> > > >
> > > >
> > >
> >
> >
> >
>
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