• Blackmagic Design

  decklink HD reference/sync prob

  Posted by Daryl Burney on October 10, 2005 at 1:33 pm

  This is a prob I don’t quite understand so I’m not going to explain it well…
  but we have a consistent sync prob when outputting to digi A500P

  decklink SD card no prob but when I install HD 444 card sync is not stable with SD A500P deck. this manifests itself as a frame of black (usually towards the end of long dump outs eg 50mins) and it also shows up when we later try to do an insert to tape and it won’t match frame as the orig dump-out drifted by a couple of frames over the period of the dump. Again insert the ol’ SD decklink card and probs are solved. We had the HD card replaced but to no avail.

  equip: tiger/latest blackmagic drivers/fcp 5/g5 dual 2.5 xserve raid.

  SD sync pulse generator fed into blackmagic card…. is this the prob? should I have a HD sync pulse generator?

  thx
  DAryl

  Luke Maslen replied 20 years, 7 months ago 3 Members · 3 Replies
• 3 Replies

• 

  Shane Chadder

  October 10, 2005 at 3:07 pm

  Do you have the same sync signal going to your deck and your bm card? The sync problems I’ve seen usually shows up as a jittery picture or the machine not able to resolve SDI audio, that sort of thing.
• 

  Daryl Burney

  October 11, 2005 at 8:17 am

  thx for your response…

  The prob seems to have been with me.
  I had my SDI (to deck) cable plugged into the SDI monitor output instead of the SDI (to deck) output.

  oops…. Interesting that the 2 SDI outputs should be a different type of signal. What is that about?

  thx
  DAz
• 

  Luke Maslen

  October 12, 2005 at 2:24 am

  Hi Daz,

  Thank you for posting your solution to the problem.

  [DAz] “Interesting that the 2 SDI outputs should be a different type of signal. What is that about?”

  The SDI monitoring output is just that.

  The SDI output to deck can be used to lock the deck to the card during capture without the need for external sync. If you check the DeckLink PrefPane in the System Preferences, you will see the option to Black video output to deck in capture”. If this is set to SDI, it will output black video to the deck’s input when capturing from the deck’s output. This is nice as it eliminates the need for and cost of a blackburst generator. However if you use house sync in a facility, then you it does not matter whether this option is enabled or disabled.

  One caveat to note is that enabling this option will mute audio on the SDI output during capture. Given you are using external sync, you may want to disable this option so that you can monitor audio during capture from the SDI or SPDIF outputs of DeckLink.

  Regards,

  Luke Maslen
  Blackmagic Design

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