So one of those things that doesn’t come up much, but is really important, is the prohibition against letting timecode go past midnight. Once it gets past 23:59:59:23 (or 29 or 24 depending on your timebase) it goes to 00:00:00:00. If that happens, how does your timecode-based editing system know that the footage with lower numbers comes after the footage with higher numbers? It’s a timecode break. Computers aren’t good at guessing.
I ran into this problem recently with a multi-camera P2 shoot using Time of Day timecode on a 2-hour show that started at 11pm. The timecode started at 23:00:00:00 (approximately) and ended at 001:00:00:00. That’s no good for FCP. What we should have done was start the time code at 11:00:00:00 instead, but the show started late, and we were supposed to be done before midnight, and nobody had planned to shoot past midnight and nobody remembered it would be a problem. The big problem I ran into was since these were 2 hour AVC-Intra clips recorded on P2 cards, everything was spanned over about 17 clips on each camera. But since the timecode reset, FCP couldn’t figure out how to combine the spanned clips into the one clip I wanted.
I could have just log & transfer imported all the individual clips, laid them out on a timeline, and then exported that timeline as one big QT file, but that would take forever to import and export since the files are so big. What I did instead, thanks to an idea from David Wulzen at Creative Cow, was go in and edit the start timecode in the Contents/Clip/*******.xml files for all 70 of the clips I wanted to span, and now FCP joins them up with no problem. Hooray for the Internet!