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A/V Synch problems after rendering with Premiere Pro 2/Help thanks

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alegator

Instructor
Aug 28, 2006
7
AR
I captured a Hi8 NTSC tape onto my PC using the Canopus ADVC100+Premiere Pro 2.The captured file was targeted to a 2nd internal hard drive and it ended up being 24.1Gb in size. I used DV-AVI NTSC Standard 48KHz project template within Premiere. I checked the captured file from start to end and the video looks fine with no A/V synch issues. So I imported this video into Premiere and generated 16 subclips according to themes. I then exported all of these subclips into movies using same video format as captured so no reconversion would happen during rendering (DV-AVI NTSC Standard 48KHz). I checked the clips and the first 5 or 6 clips look fine but as I check later clips there's a gradual A/V out of synch issue that gets worse in the last clip. So what happened? How come original captured file is perfect and after rendering the subclips with Premiere they turn out to have this A/V issue? How can I prevent this from happening?
this is what I did. I first imported the original captured file (24.1 Gb, no A/V issues) into the Premiere Project asset list. I dragged that file into the Source Monitor and as you say I marked several In and Out points generating the 16 subclips in the process. The way I did this is once an in and out point was marked I right clicked on the source monitor and I chose "Make Subclip...", this generated the subclip to be listed automatically in the assets window together with the original captured file. Once all subclips (16 in total) were created in this way I exported the clips to the corresponding movie files with the same video settings as the captured file so no reconversion would happen during rendering. The way I exported the clips was by dragging each subclip into the Timeline Sequence window and then from the menu File/Export/Movie..., choosing the 2nd drive (where the orignal captured file is) as save location.This routine was done 16 times , once for each subclip.
By "themes" I mean my criteria for setting in and out points according to the subject in the footage. I don't think I altered any other parameter like speed, etc. I left all other options/settings in Premiere untouched.
Just to add more info, I did all of the following:
1) The A/V synch problem is independent of the player used, I viewed the rendered movie in the monitor window within Premiere, in Windows Media Player, Nero Showtime, Cyberlink PowerDVD, etc...they all show A/V synch problem. (Audio comes out form the PC speakers using internal sound card).
2) I rendered the same subclip with other video editing software (using the Premiere captured file as source) and there is NO A/V synch problem in the rendered file (I tried Windows Movie Maker and Ulead Video Studio 10 Plus).
So the problem arises in the Premiere rendering process. I have no idea why Premiere is generating this problem. I'm starting to think that it might be hardware related?? I'd appreciate any suggestion to fix this, thanks!!


 
There has been an issue with some Canon equipment generating audio files that are not quite at the sample rate that they claim to be. Thus, when taken at face value by NLE, the audio steadily drifts on very long files. No idea if this might apply to your setup, but it looks suspicious.

You might be better off capturing in smaller chunks using a program like Scenalyzer Live, which also has a facility to lock audio to video during capture. Have a look at for try before buy (fully functional but video watermark until registered).
 
Thanks, I'll take a look. Is there a way to lock audio during capture using Premiere Pro 2?
 
Can't asnwer that. I have only 1.51. But not in 1.51.
 
Just an update. I experimented rendering the subclip with Premiere using a different method and it worked fine, the rendered movie has NO A/V synch issues. This is how I did it: instead of generating subclips I double clicked the captured file making it appear in the source monitor. I marked the in and out points for a given clip and instead of generating a subclip I dragged directly the marked clip in the source monitor onto the timeline sequence. I then went to FILE/EXPORT MOVIE. It seems that generating subclips in the asset window slows Premiere and creates this issue in rendering.
 
I would doubt that sub clips are the issue, since they are only internbal pointers into the file, not true 'clips' at all.

More likely that the 'cure' you have invoked takes short sections during which the audio drift is insufficent to show up.

Anyway, glad you've found a workaround.

Think about Scenalyzer Live if you want to capture any more of this type of material.
 
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