I made digital conversion's of old video tapes, the video files are 25 frames interlaced, when I play this video the audio and video are perfect in sync, after I import it to Vegas Pro 20 the audio is out of sync. I try to correct this but after rendering its out of sync again, what goes wrong here ? Is deinterlacing from 25i to 50p the problem ?
Is deinterlacing from 25i to 50p the problem ?
No, frame rate doesn't normally affect audio sync in Vegas. Can you upload a short actual conversion to Drive or Dropbox?
Is it constant out of sync, or does it drift?
Yes its constant out of sync, its strainge that I can sync the audio in the edit , but after rendering its out of sync again, I am looking now at the way my videocapture device is proces the capturing.
Have you used MediaInfo to see if the video is a constant frame rate one?
Thanks for the tip, I will analyse it I am thinking in that direction too because its a very old tape (1990), and tape can stretch out abit.
It's easy to use, and it's free. View>Tree and look at Video>Framerate and make sure it says Constant. If it says Variable, look at the actual frame rates and see if there is a huge swing in it.
I see now what the problem was, my capture device made mpeg2 files, those files can,t be handel properly by VP and other edit software, I switch now to MP4 files and now the sound is perfect in sync. Thanks all for your help.
MPEG-2 is generally rock solid in all versions of Vegas Pro. Capture devices in themselves are notorious for lateral sync errors and drift with analog source. That said, congratulations on finding your own solution.