Freaky double framerate problem – 25fps footage plays at 50fps
I captured hours of footage from a DVCPRO HD tape deck (1080i 25 PSF) into Apple Prores (HQ) 1080i 50. The footage has a weird problem:
When I play it back in quicktime, the info window reports the file’s framerate at 25 fps, but it plays the video back at 50fps. This playback error happens acros multiple systems in QT 7.6 and QT x (snow leopard).
I open the files in FCP, and throw one on a new timeline, and accept the settings that it applies to the timeline – 1920 x 1080, square, upper field first, Apple prores (HQ), timebase 25 fps. And with these settings, on this timeline, it plays back the file right. Perfect. 25fps.
But I have no way of getting it to standard def. Because if I throw the clip on a PALtimeline (DV, Prores, Prores (HQ) – whatever), it has a green bar and needs to render. AND IT RENDERS THE FOOTAGE in 50FPS! everything plays double speed and goes out of sync since the audio is not affected. Audio plays at the right speed everywhere.
At this moment it seems my only way forward is to play the footage out of this system over HDSDI and recapture it on another system in another codec, and test it. DVCPRO HD codec…
Weird, don’t you agree? Anybody seen this problem before? I run a studio where we capture 1080i 25 direct to apple Prores on Kona cards and have never seen this problem before.
The system I captured on is a brand new Mac Pro 4core, with Decklink Studio card, os X 10.5.8 and FCP 6.0.5. We tested playback on several systems (leopard, snow leopard, G5 and Intel) and they all play back the same way – so it has something to do with the captured files.