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Audio sync drift problem with HVX200 P2 capture
I’m not sure if this is a question for the Panasonic HVX200 board or FCP board but..last night a friend brought me some footage to capture and i encountered a baffling technical glitch i’ve never encountered before with that camera.
Footage was shot 720 30p, capture and project settings were all matched, the footage was fine and IN SYNC when played back ON the camera, but when and after capturing it drifted out of sync
Regardless of which method i used to capture/import the footage into FCP (trying it on three different computers no less) The audio would drift out of sync almost instantly, though very randomly and erratically at times with various clips. Meaning sometimes a clip would capture and it would hold in sync for a minute then drift out, sometimes drift out of sync after 3 seconds!
I tried capturing both ways (via FW and USB 2.0) and the play-back streaming method (via FW) on both FCP 6 and 7 on a G5, Intel MiniMac and Intel Promac. Sound sync would always drift. The sound was always ‘faster’ than the image
Has anyone ever encountered this before?? Any idea’s? One theory was that the camera settings in recording format and shutter speeds were somehow mismatched or improper but would that cause audio to drift after a capture??
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27 Replies
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Why not just take the footage off of the p2 cards?
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well,..that’s what i’m trying to do
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So tell me exactly what you did. Camera menus and everything. From your post, it’s not quite adding up. No offense, just helping.
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Yea there may have been something in the camera settings that was off, like frame rate, recording settings i’m not sure. It was shot in 720, 30p (regular not native) thats all i know (i didn’t shoot the footage) But i’ve never encountered a situation where audio drifted after capturing, it’s really baffling. Personally i’ve shot tons of footage on the same model camera and haven’t always been careful about matching frame-rate/format settings and all that jazz and it was always ok
My only guess is it’s some bizarre glitch no human has ever encountered
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So you have the footage transferred off of the cards?
Please give me the play by play.
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Damon,
I don’t know if you solved your problem, but I have a similar baffling issue. I have 23.98 footage shot on both the 7D and T2i, transcoded to one long clip using MPEG Streamclip. When I play the transcoded clip in QT or in the Finder, it’s perfectly fine. When I drag and drop it into FCP, then play it in the Viewer, the audio drifts. This only happens with footage that is 23.98. I transcoded those original files to 29.97 (even though they were shot in 23.98) and the resulting file did NOT drift.
What’s weirder is that I have some other 23.98 files which also do NOT drift. Those are clips I created earlier in the year. I can’t find a consistent pattern. I’ve tried numerous clips and dozens of tests and can’t nail down a consistent source. The closest thing I can determine that it’s 23.98 footage created after a certain date.
I’ve posted on the Cow and a few other forums, and no one can figure it out. Your problem seems like the same issue I’m having. At least I’m not alone.
Ron Dawson
Executive Producer/President
Dare Dreamer MediaCreating films that inspire and encourage the human spirit.
*** Dream Out Loud ***
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[Ron Dawson] “When I play the transcoded clip in QT or in the Finder, it’s perfectly fine. When I drag and drop it into FCP, then play it in the Viewer, the audio drifts. “
Is this embedded or separate audio? You have transcoded the file to 23.976 not 23.98, right? There’s a big difference.
Jeremy
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Hi Jeremy,
I transcoded the clip to 23.98. That’s what I’ve always done and have never experienced this. It’s the most baffling thing.
Here’s my latest update: I discovered that 29.97 footage does not drift when imported into FCP. I transcoded the original h.264 files (shot at the 1080 24 on the 7D) and this time transcoded them to 29.97, and the drifting does not occur. The downside is that I don’t want 29.97 footage, I want 23.98.
I would make the conclusion that 23.98 footage is the culprit, except that there are SOME 23.98 clips I have which are also fine (i.e. don’t drift). But, somehow the drifting seems tied to 23.98 footage shot after a certain date.
Ron Dawson
Executive Producer/President
Dare Dreamer MediaCreating films that inspire and encourage the human spirit.
*** Dream Out Loud ***
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Should always be 23.976. 23.98 is shorthand for that in FCP.
Again, is this separate audio or embedded?
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Thanks for the transcoding tip. Will definitely keep that in mind.
Anyhoo, it is embedded audio. Clip plays fine when played in QT or the Finder. Once imported into FCP and I play in the Viewer, I get the drift. Gets progressively worse as you get to the end of the file. The longer the file, the worse the drift gets. For one 3.5 hour file it’s as much as 22 frames.
Ron Dawson
Executive Producer/President
Dare Dreamer MediaCreating films that inspire and encourage the human spirit.
*** Dream Out Loud ***
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