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Poor playback in fcp7 prores 422 LT 50fps
Dear Super-Pros,
I’m having trouble playing back 1080p 50 fps footage in a 50 fps sequence on fcp7 / macbook pro 10.6.8 2.4 GHz Intel Core i5 > 2 x FW800 2TB WDs. I’ve used this kind of footage before, never had the stuttering issue that now jumps me sometimes up to 1 sec at a time, audio plays back continuously. This is regardless of RT settings, have tried them all. Footage recorded on Sony NEX to MTR files, converted to ProRes 422 LT with AVCHD Converter @ 1920×1080 50p.When importing to FCP I get a warning that says “media not optimized for fcp…” but pertaining to multistream playback which is not my issue. It’s as if my MB were too slow all of a sudden. Can the external HD be too slow or too full (at appr. 65%)???
AVCHD Converting video settings were: Apple ProRes 422(LT), 50 fps, resolution smartfit or 1920×1080, bitrate 2000 kbps.
Help please! The idea of having to re-convert 2 TB of footage is a nightmare, and I have a deadline!
Thanks, it’s urgent 🙂
Michael Brown
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3 Replies
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I might add that the only noticeable difference was the bitrate @ 2000 kbps (instead of formerly by default 1500).
Michael Brown
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You got that warning because 1080p50 isn’t a normal format. It is becoming a common shooting format for some reason, but not one that has a deliverable. Broadcast doesn’t do 1080p50 (or 60)…BluRay doesn’t…and it isn’t seen much on the web due to the high data rate required to stream it. THe main function of 50p or 60p is to slow the footage down to more standard frame rates…25 or 30.
If you say the only difference between the files that worked, and the ones that don’t, is the bit rate…then that’s it. You should stick to the default. Raising the bit rate makes the files have a higher data rate, thus requiring faster drives to play back…faster than FW800. 1080p50 has a high data rate as it is.
Shane
Little Frog Post
Read my blog, Little Frog in High Def -
Hey thanks Shane, I suspected so much, But it might be interesting to note that I found a rather simple solution: I got curious as to whether specific items on my timeline were giving me trouble, and just out of curiosity I shut off a music track and bingo! Sound seems to be a major issue! When playback begins to stutter, all I have to do is render audio (which goes a lot faster than video of course), and playback is then smooth. My video sometimes asks for rendering (green) because I also mix frame rates (25/50) and I’m working on 50 fps sequences (intentionally for much smoother results due to shutter speeds & fixed focal lenses etc).
Maybe you have an idea as to why the sound is so relevant. I do import it @ 48 KHz 32-bit floating point, and the timeline doesn’t appear to require audio rendering, but when I do so anyway, audio indeed renders.
I’ll have learned from this experience. If you get around to giving this sound thing a second thought, I’d be interested.
Take care and many thanks!
Michael Brown
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