FCP export problems….Help!!!!!

[Ben Holmes]

Can you explain what you mean by ‘jittery’. Do you mean it looks like field jitter (although I appreciate you are working in 720p) – in which case have you tried deinterlacing on export to eliminate this (somewhat unlikely) explanation, or do you mean you are seeing jitter on motion or dropped frames? A little more info on this would help.

My first suggestion would be to make some of your footage/exports available to people here, to see if they can diagnose the issue.

Ben

Edit Out Ltd
—————————-
FCP Editor/Trainer/System Consultant
EVS/VT Supervisor for live broadcast
RED camera transfer/post
Independent Director/Producer

[Stuart Simpson]

If you play the P2 files out of the camera into a monitor is the “jitter” present?

-Simmie
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[Mario Fontana]

Thanks for the replies. The video being shot looks fine when viewed right out of the camera from the P2 card. We did a “tape” feed last night from a production truck and everything was perfect.

A copy of yesterdays report we sent can be found here: https://www.mediafire.com/?sharekey=592802aa60024d5a931c7453395df025e04e75f6e8ebb871

You can see the “jitter” even on these talking heads. I can’t see it fully as I am on the road and the broadcast version of this isn’t available where I am but I am told it looks like it has been shot on film.

Thanks very much guys. May the suggestions keep on coming.

[Mario Fontana]

I have uploaded two files here: https://www.mediafire.com/?sharekey=592802aa60024d5a931c7453395df025e170d73323e645cfce018c8114394287

One showing yesterdays report and the other showing some fast motion of guys skating to really emphasize the problem.

Thanks

Mario

[Larry Asbell]

You are shooting at 60P. When you export at 29.97 your export is throwing away every other frame.

You can’t do this and expect the result to look the same.

[Mario Fontana]

Thanks Larry. What would you suggest we do? Should we change shooting mode? Is there anything on the timeline we can do? Any settings within FCP?

Thanks

Mario

[Larry Asbell]

Well for starters, you could check to see if I correctly fingered the cause. Re-import your export into FCP, put it in a sequence, set playback to Safe RT so it won’t drop frames and compare the original and the export. Watch them at play speed and advance them frame by frame. I believe you’ll find that the original has “finer slices” of the action and twice as many of them.

What do you do?

1) you could export your good looking original at at it’s original frame rate. Sure, it will double file size but you can lower the date rate by adjusting the amount of compression if you need to.

2) Less effective would be to shoot in 30P and make sure the shutter speed was long enough so each frame had a more blurred action rather than stop-action look. Somewhere in the neighborhood of 1/60th sec, i.e. 180 degree shutter. This will naturally blur fast action and allow the viewer’s eyes to see the action of each frame “meld” with the one before. I don’t really believe you will like the result anywhere near as well as option 1. I mostly suggest it to help illustrate the principles involved.

Remember both broadcast specs for HD sample action 60 times a second. 1080i is 30 frames per second, with two interlaced fields in each frame, i.e. 60 fields per second, and 720p is 60 frames per second. There’s a reason they chose those rates.

You may say, Yea but film has been shot at 24 fps since the invention of talkies. That’s correct but cinematographers keep the shutter speed slow enough to blur the action, avoiding the look you are getting.

– Larry Asbell