• Blackmagic Design

  FCP + decklink studio exports sped up video at 49.95 fps

  Posted by Ryun Hovind on January 6, 2011 at 7:41 pm

  Hey guys,

  I have a problem. I am capturing HD files that play back fine in FCPro, but if I export them the video speeds up rapidly, becoming out of sync with the audio. I called Black Magic and they didn’t know how to help.

  The capture settings were:
  BlackMagic HDTV 1080i-59.94 – Apple ProRes (HQ)

  The path was we shot with a Sony (HDV cam) and ran it through a Black Magic HDMI to HD SDI converter which then went to a Datavideo switcher (via HD SDI) and then into the Intel Mac which uses the Decklink Studio card. The signal went into the computer using HD SDI cable at 59.94 fps.

  Once captured the files were plopped into a ProRes (HQ) sequence and the files play back fine in FCPro. However when I export them doing a straight “Export QT Movie” command and try to play them back in QT Player, the audio in and out points stay true but somehow the video gets all sped up.

  I analyzed the captured clips in Cinema Tools and it said they had a 49.95 framerate. If you analyze the short clips in the link I provided they say the video is 29.97, but that’s because I exported them out of FCP.

  This link expires soon but here are some examples:
  https://www.yousendit.com/download/RlRya3ZFNkdPSHp2Wmc9PQ
  https://www.yousendit.com/download/RlRya3ZLUENCMTQwTVE9PQ

  I appreciate your help ladies and gents.
  Ryun

  Just what is it that I don’t get?

  Ryun Hovind replied 15 years, 7 months ago 2 Members · 3 Replies
• 3 Replies

• 

  Shane Ross

  January 6, 2011 at 8:05 pm

  Why not take that clip into Cinema Tools, and use the CONFORM option to conform the clip to 29.97? There might be something screwy in the metadata that CT might be able to fix.

  Shane

  GETTING ORGANIZED WITH FINAL CUT PRO DVD…don’t miss it.
  Read my blog, Little Frog in High Def
• 

  Ryun Hovind

  January 7, 2011 at 11:46 pm

  I brought a clip into Cinema Tools and conformed it to 29.97. The footage remained out of sync with the audio, but both the audio and video were sped up by the same increment.

  So I then took the new video clip which was 29.97 and brought it back into Final Cut. In Final Cut I multiplied the audio speed by 1.67 (49.95 fps divided by 29.97 fps = 1.6666666666) and it synced back up with the 29.97 video. However, these conversions resulted in quality loss in the video and an increased noise floor in the audio.

  Any further thoughts or other suggestions would sure be appreciated.

  Ryun

  Just what is it that I don’t get?
• 

  Ryun Hovind

  January 11, 2011 at 9:53 pm

  I have found that if in my Final Cut Pro sequence I appy a speed conversion (ie SLOW down the video to 59.99988%. I got this by taking 49.95 fps and dividing by 1.6667 to make the video 29.97) then the audio and the video match up when I do to export movie.

  There is definite frame conversion artifacts for the output Quicktime, but they sync up so I am STILL anxious to have someone a better way of doing this. Plus I need future captures to be clean.

  If someone has any suggestions for setting up DeckLink Studio with FCP 7.03 so this problem won’t occur please let me know. Thanks,

  Ryun

  Just what is it that I don’t get?

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