Latest post Sat, Jan 26 2008 5:02 AM by dekafilm. 6 replies.
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  • Thu, May 24 2007 9:36 PM

    • jdd1904
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    Timecode Offset

    Hi. Sorry if this is a stupid question, but here's my situation: I'm attempting to capture some footage from a digi-beta source (Sony DVW-A500 deck), but the TC coming via the RS-422 is 1 frame off from actual TC on tape (this has been confirmed by capturing from the super out from the deck). I know there is a TC offset when capturing via firewire w/RS-422 control, but how about when capturing component through the mojo? I've been through the manual & help files, but I can't seem to find the TC offset for non-DV material. I don't have this problem with other decks (e.g., Sony J-H3/HDCAM). Is there a TC offset? If so, where?

    Here's my setup:

    Xpress Pro HD v. 5.2.4
    Mojo (non-SDI)
    HP Workstation xw8200
    Xeon 3.40GHz, 2.00 GB of RAM

    Thanks in advance for the help.

    Jay

    Mac Pro 3,1 2x Quad-core Intel Xeon ATI Radeon HD 2600 10 GB Ram Matrox MXO [view my complete system specs]
  • Tue, May 29 2007 5:45 PM In reply to

    Re: Timecode Offset

    try using the audio delay setting in the capture window. I find that also delays the TC.

    run a test, capture with audio delay at 0 with TC burned into the screen.  then check the burn in against the TC the avid's has for that clip.

    then adjust the Audio Delay on the Capture window and capture again with the Burn in.  Then check the burn in against the avid's TC.  if they match, then you are good to go.

    Follow me at www.twitter.com/redarrowryan [view my complete system specs]
  • Fri, Jan 25 2008 2:12 AM In reply to

    • dekafilm
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    Re: Timecode Offset

    mr_difficult:


    try using the audio delay setting in the capture window. I find that also delays the TC.



    This is an old post, but I didn't want anyone to think this was a proper solution for everyone. From the MC 2.8 manual:

    "If the audio you are capturing is always at a fixed offset ahead of the video, use the Delay Audio feature to correct this problem and produce a master clip with correct A/V sync."
    The manual mentions this specifically in connection with footage from cameras, like the Panasonic AG-DVX100A, that are known to have a consistent audio delay in certain shooting modes.

    ...in other words, the "Delay Audio" setting in the Capture tool actually throws your audio out of synch! It is NOT intended for the problem mentioned in the original post, in which a deck inaccuracy or RS-422 communication issue throws off only the *timecode* (while audio and picture remain *in* synch with one another).

    Case in point: the Telecine tapes I'm working with from a reputable post house here in LA are spot-on. Introducing an audio delay would completely mess things up. Meanwhile, my DVcam deck is intermittently a frame off. This is evidenced by:

    - KeyKode, video timecode, and audio timecode windows are all a frame off vs. what the Avid's logged clip states (window burn vs. Avid's numbers over the Source window)

    - 3:2 pulldown removal from Telecine is not working (motion stuttering and strobing fields)

    Sometimes just recapturing the clip gets it in the groove. Sometimes it works the first time. If your dailies are on DVcam, too, you'll probably have an error rate of about 10% of your clips. Useless aside: BetaSP was almost always perfect, once calibrated. Progress.

    Which brings me to my problem: I have an error rate of about 50% of my clips with my current setup (see below). This means that checking each clip and redigitizing the bad ones is too hit-or-miss (two hours of dailies have chewed up an entire day!) My feeling is that I have a 1-frame offset *in addition to* the usual DVcam inaccuracies. This is what I need to fix (without breaking anything else!).

    So does anyone know of any console commands or other adjustments that can be made to introduce a 1-frame offset using RS-422 on a DSR-2000A via Keyspan (Mac Pro, MC with Mojo SDI, coming in over SDI in a 23.976 project)?

    Any help is appreciated! Thanks.
    AVID Media Composer v8.x MacPro 2010 (5,1) 12-core running OSX Mavericks and Sierra, 24GB RAM stock ATI Radeon 5770 graphics card AVID Media Composer... [view my complete system specs]

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  • Fri, Jan 25 2008 8:19 AM In reply to

    Re: Timecode Offset

    Also, the burnin window on a DB will be 1 frame off if is placed in the top 25% of the image.
    Media Composer Symphony | PT Ultimate | Win10 HPZ | OSX MBP | ISIS5000 [view my complete system specs]
  • Fri, Jan 25 2008 7:50 PM In reply to

    • dekafilm
    • Not Ranked
    • Joined on Thu, Oct 13 2005
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    Re: Timecode Offset

    Wow, I've never head that about DigiBetas! Is that for all decks, or just some? It's just as horrific as sound and picture being out of synch, but only in certain frame modes, on the Panasonics. Again, progress... Meanwhile, still no solution to the RS-422 deck control offset issue. Anyone?
    AVID Media Composer v8.x MacPro 2010 (5,1) 12-core running OSX Mavericks and Sierra, 24GB RAM stock ATI Radeon 5770 graphics card AVID Media Composer... [view my complete system specs]

    http://www.davidekabramson.com

  • Sat, Jan 26 2008 4:53 AM In reply to

    • jwrl
    • Top 25 Contributor
    • Joined on Thu, Oct 13 2005
    • Melbourne, Australia
    • Posts 8,427
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    Re: Timecode Offset

    dekafilm:
    Wow, I've never head that about DigiBetas! Is that for all decks, or just some?

    All decks, and it also happens on Beta-SP.  Except in that case it's the top half of the screen.

    MC 7.0.4 - Asus P6T Deluxe V2 mobo - Intel i7 920 2.66GHz - Windows 7 Ult64 SP1 - nVidia Quadro FX 1800 - 16 Gbyte low latency DDR3 RAM - Internal 8 Tb... [view my complete system specs]
  • Sat, Jan 26 2008 5:02 AM In reply to

    • dekafilm
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    • Joined on Thu, Oct 13 2005
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    Timecode Offset - SOLUTION FOUND

    Talking to folks over the past two days, I got all KINDS of suggestions (more below). But what worked for me is this:

    Instead of using the intended deck template for the DSR-2000, I switched to 'Generic Editing Deck, NTSC' as my deck template. I went from 50% of my clips being 1 frame off to absolutely 100% being accurate! This is on a sample set of roughly 90 clips, including some that had previously been intractible.

    Credit for this goes to Electric Picture Solutions. Thanks guys!

    Also suggested, but completely ineffective for me:

    - swapping serial ports on the 2-port Keyspan adaptor (no effect)
    - swapping USB ports for the Keyspan adaptor (no effect; idea was that USB bus latency may be affected)
    - updating drivers on the Keyspan adaptor (no effect)
    - changing from SDI to analog input (no effect)
    - using/not using the 'Super' output, with or without timecode characters turned on (no effect)
    - switching from VITC to LTC on the deck's front panel (actually, LTC showed a *minor* improvement over VITC in my case, but not nearly enough to make a difference)
    - swapping decks to eliminate alignment issues (e.g.: pinch roller; almost happened, but wasn't necessary)

    For each suggested fix, I tried ten or more clips, so the results are statistically acceptable. And you can't beat suddenly achieving a ZERO error rate. :o)
    AVID Media Composer v8.x MacPro 2010 (5,1) 12-core running OSX Mavericks and Sierra, 24GB RAM stock ATI Radeon 5770 graphics card AVID Media Composer... [view my complete system specs]

    http://www.davidekabramson.com

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