Why isn’t the original 5D synced? was it a double sound system and they screwed up on the production speed? You can find out how badly they recorded by aligning the rate stretch tool in premiere with the waveform lip sync.
Compressor has less artifacts than twixtor, but you can’t optically change the fps because your audio is out of sync to begin with! FCP needs all footage to have the same fps.
This is what I would do.
1. If I couldn’t find out the production sound speed, I’d sync up the audio to the original with premiere’s rate stretch tool to the waveform of obvious silibants. (The farther away the 2 wavecrests you choose, the more accurate the sync)
2. Once synced up, I’d open compressor, click conform to 29.97, or timestretch in AE,(will then slow down both the video and audio to 29.97.) or optical flow.
3. edit in FCP then master in pro-tools.
The reason you can’t take any shortcuts is because your framerate is messed up too, not just your unknown audio speed.
And if this sounds like a nightmare, hire a better crew next time.
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