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DVCPRO HD frame shifting bug glitch – and workaround
I’m using DVCPRO HD 23.98 footage, that was imported back when the HVX-200 just came out. It’s showing unusual behavior in FCP. Any information about either of the bugs we’re seeing would be really helpful.
Having your project set to DVCPRO HD 23.98, and watching the footage dropped into the timeline (native) looks frame-accurate to watching it in quicktime. Specifically the first three frames of the clip have distinct frames.
and here is where is gets weird
when you have have a clip in FCP native (no RT effects), and then export that to a QT file, the first three frames are fine (1,2,3)
when you put any RT effects on it it looks fine in FCP playback, BUT when you render out to a QT file – the resulting QT file has 2 double frames and then frame 2 (so 1, 1, 2) at the start. This doesn’t happen at the start of a cut, cuts are retained, but each clip is shifted over by 1 frame. Sound stays the same we think.
also, when you put any non-RT effects on it, and render it for
playback in FCP, the same happens right in front of your eyes on the timeline, all the clips get shifted over.So basically, any DVCPRO HD footage that we’ve rendered out shifts over, if it has RT effects on it like Chroma Key, or non-RT effects on it like a 8 point mask.
The workaround we’re exploring currently is batch-confroming all the footage with Cinema Tools to 23.98 (which is what it claims it is). And then the clips behave in FCP, no frame shifts like before. What’s good about Cinema Tools, is that it doesn’t re-compress the clips and you can batch conform in little time.
So we’re wondering if this problem has something to do with the early FCP HVX-200 importer. Some of the clips we captured real-time, and some we downloaded off P2 cards using FCP’s p2 card interface.
The only problem with the Cinema Tools, seems to be a quicktime / shake bug. When you conform a HD 720p file, cinema tools seems to set the default QT viewing size to half. This doesn’t affect FCP, as it thinks the clip is 720p. It does present a problem for Shake apparently, as a files default QT size is interpreted as the
resolution. Setting the file to “Actual Size” in QT and simply hitting “save” seems to solve this issue, and Shake interprets the footage at full resolution.So there you have it, 2 glitches that are happening in our pipeline. Any info would be extremely helpful.
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4 Replies
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I have never encountered this before…
I’ll have to ponder this one out…odd.
Shane
Littlefrog Post
http://www.lfhd.net -
[gingerbreed] ” that was imported back when the HVX-200 just came out.”
You mean it was imported with FCP 5.0.something and now you are using it in FCP 5.1.4 or FCP6?
See this ole doozy as it might pertain to you:
https://docs.info.apple.com/article.html?artnum=303950
Jeremy
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Thanks so much, you have solved the riddle of the duplicate rendered frames!
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No worries and glad it worked for you.
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