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mann1970
06-25-2003, 02:28 PM
I am capturing live interviews using BoB, (capturing as RTV) switching between cameras. Once we are done and put my 10 minute long clip on the timeline, my audio is not in synch with the video. This synch issue is very noticable in the later part of the clip. Is their any fix for this issue.

Thanks
Gary

Dan Hong
06-26-2003, 08:59 PM
Are you capturing with analog video in (on the bob) or are you using firewire? Also is the audio coming into the bob or is it going through a mixer first. Lots of issues could be to blame. Tell us more about your system and wiring.

mann1970
06-27-2003, 09:17 AM
I am using BOB and coming in using SVHS for Video and also I am coming directly into bob for my Audio. I am capturing my video as RTV format.

SBowie
06-27-2003, 06:17 PM
Check the Capture settings to see whether or not you have it set to stop recording on dropped frames - if not, and if you're dropping frames, the result can appear like audio out of sync. Also, see that you are (normally) recording the Program Out, not Main In.

stuart_tetley
07-08-2003, 01:24 AM
I initially had this problem with capturing from video tapes (mainly oldish VHS tapes.) I tried various suggestions, mostly revolving around beefing up my (initially nonexistent) RAID array. None of this helped a whole lot, though I now have a decent disk system.

After all that, Steve's simple suggestion of capturing from Program Out (which I understand brings the Toaster's Timebase correcter into play) rather than Main In, eliminated the problem completely.

mann1970
07-08-2003, 08:01 AM
I have also changed my settings to program out and hopefully this should fix it. Thanks to Steve!!

SBowie
07-08-2003, 11:57 AM
Quite welcome. :)

My thinking on this is as follows: your system is perky enough throughput-wise to record uncompressed without issue, but the source is not as stable as desirable. Capturing from 'Main' requires a fairly rock-solid sync. If it doesn't get it, and if 'Stop on dropped frames' isn't enabled, you'll drop frames - and the audio will creep out of sync with the (shorter than it should be) video.

Capturing Program allows the VT to sidestep the issue, 'stretching' frames as necessary. In this case, it's really more than likely a source quality problem, not a VT or system problem.

stuart_tetley
07-14-2003, 03:13 PM
That tracks - I was capturing VHS - probably about the worst thing to be working with....

Curiously, though, I had 'stop when frames drop' enabled the whole time, and it didn't stop by itself even once.