"The problem I fear is that if I'm locked to external reference while recording something that may be locked but way out of time and during the recording everything looks okay E to E but then I go to playback the tape and the video plays back a 3rd of a field down with a bunch of sync cross hatch type stuff."
Well then lucky for all of us, the 5500 has a Confidence head, something that has been around since the digital SD days. Monitor off the Confidence head, and you'll have layoff and QC done in one pass - hence "confidence".On Tue, Nov 12, 2013 at 7:36 PM, johnrobmoore <bigfish@pacbell.net> wrote:
Look I'm all for external reference. The problem I fear is that if I'm locked to external reference while recording something that may be locked but way out of time and during the recording everything looks okay E to E but then I go to playback the tape and the video plays back a 3rd of a field down with a bunch of sync cross hatch type stuff. It's been a long time since I've had that happen but those scars are still there. That's why I felt it would be safer to lock to internal video for blacking from the internal signal generator. Apparently it's not but I've been asking this over and over for years and even the Product Support people at Sony haven't given me a convincing answer to the internal signal generator reference. I kind of feel like Bob Z use to about how to properly reference the BVW 1800 decks using a short piece of coax looping from the machines video input because he couldn't get them to play nice any other way.
--- In Avid-L2@yahoogroups.com, Mark Spano <cutandcover@...> wrote:
>
> Here's my bottom line on reference:
>
> What do you trust for clock timing? Your computer, or your ref generator?
> Me, I've seen so much bad and weird video that comes from computers
> (whether they be FCP / Avid / AJA / Nitris DX / BlackMagic / etc.) that I
> have no faith in it for a solid reference. So I (and my entire 14-bay
> facility) never do anything on these decks that requires changing the servo
> off of External for reference. Well, except when you're using that good old
> Teranex which throws timing out of whack.
>
> To me, any discrepancy in timing in my facility comes from the computers.
> And that gets resolved instantly by choosing External Ref in the Video
> Output Timing selector in your Avid (or Ext Ref setting in your AJA).
> Choosing Input as your servo reference is just a simple way to get a job
> done and it's fraught with potential problems. My whole job is to root out
> potential problems and turn them into non-existent problems, and this is a
> perfect case. Clock everything to one master reference generator and you
> bypass problem city.
>
> If your cable runs are extremely long for composite video (aka Ref) then
> you can run into issues. Always measure timing and integrity at critical
> points and keep runs short enough to eliminate noise. DA at regular points
> and life is good. I've got 14 bays on the 8th, 6th, and 3rd floors of this
> NYC building all locked nicely to one constantly running reference master
> clock.
>
> "Virtually every "VTR Tech" I meet from rental houses always suggests using
> video input servo reference"
>
> 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…
>
>> On Tue, Nov 12, 2013 at 7:06 PM, johnrobmoore <bigfish@...> wrote:
>
> >
> >
> > Be careful because if the Avid burps on output it often will send unstable
> > video to the record machine before the machine has dropped out of record.
> > This results in what acts like a control track break and even if it's not
> > technically a control track issue the only solution is to do an assemble
> > edit from that point on. This can be catastrophic if you are punching a fix
> > into a completed master.
> >
> >> > --- In Avid-L2@yahoogroups.com, <jciron2005@> wrote:
> > >
> > >
> > > I've been using Input Video for about a year on HDCAM 55's & 5800 with
> > no problem.
> > > It would not be my best choice but I had to one day and it worked great,
> > so I've been doing it ever since
> > > with no problems
> > >
> > >
> > >
> > > ---In Avid-L2@yahoogroups.com, <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 mailto: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 mailto: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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