Capturing 29.97 fps source in virtual dub at 23.976 fps?

[DJRumpy]

Has anyone tried this? I'm converting my VHS collection to DVD. Virtual dub is reporting dropped frames while capturing. This is not the case when capturing at 29 fps. I'm assuming this is because virtual dub is simply dropping frames to meet my settings.

Does anyone have any experience with this? I've done short captures, and the quality appears to be ok. The audio seems to stay in syc as well. I just find it alarming that vdub is reporting so many dropped frames.

I want to capture using 23.976 (Film) to leave more room for bitrate.

[adam]

If your source is 29.97fps, which any tv capture will be, then you cannot capture at 23.976fps.

Film is telecined from 23.976fps to 29.97fps, it is interlaced then certain fields are duplicated every second. To reverse this process you must remove these new fields. If you simply capture at 23.976fps then you are randomly skipping fields, which will cause jerky playback, possibly desync, and interlacing artifacts.

You need to capture at 29.97fps and then perform an inverse telecine, if possible. Not all sources can even be IVTC'ed. Also you dropping frames may even be a result of something else entirely, but try capping at 29.97fps and see how things go.

[DJRumpy]

Thanks Adam. Your the one who actually got me hooked on the Film frame rate 8)

I was supprised that the capture appears to be ok, even with the dropped frames. Even the audio stayed in sync. I didn't know if Virtual dub was performing an Inverse Telecine for me, hence the higher utilization, and dropped frames, or if it was simply dropping frames to get from 29 to 23. It appears to drop them in a way which makes it un-noticable.

If I do my cap in 29fps, what tool would you suggest to do the ivtc?