Frame Judder Stutter...UGH!

Greetings!

Not quite sure where to post this, but I think the FCPX group can probably help me figure this out...

No matter what I do, I keep getting judder/stutter in clips featuring pans and tilts. Generally, this is my workflow:

I shoot on a tripod with a Canon XF-300 in 1080 30P, using moderate speeds during pans and tilts. Sometimes...okay oftentimes, I may forget to turn off the XF-300's IS setting. Things look fine in the camera. I import my clips into FCPX, optimizing the video. I generally put automatic stabilization on pan/tilt clips to smooth out any wrinkles. I export to ProRes 422, drop it into Compressor, and that's about it.

Regardless of whether it's in the timeline, the ProRes 422 master file, or after using Compressor, shots with pans/tilts always seem to stutter/judder like they're dropping frames or something. They just don't playback smoothly.

Any ideas on what I'm missing here? I've researched this online and have found others having similar issues. Should I not be optimizing my native MXF video files when I import into FCPX? Should I be shooting with different frame rate settings? (Most of my stuff is for the web, but I also shoot commercials) Is it my 2011 MBP? Is there some sort of compression issue going on that I'm missing? Did anyone really care what color the dress was?

I really need some input from the forum gurus!

Thanks!

Hi August Heat

I had the same problem when I first used a Canon XF305. And, as you hinted, it was caused by the IS trying to steady the shot. On fast pans, you won't see much difference but on slow ones you do. Do a quick test: slow/medium pan with IS on and one without. Hopefully that will show you the cause.

Good luck.

First of all I'd like to ensure you that all of the frames are in fact in the video file. They're just being dropped during playback. If you burned onto a Blu-ray disc you'd see that the judder is perfectly consistent. Unfortunately for one reason or another, playback on computers rarely play without dropping frames here and there. Usually this is unnoticeable but on things with smooth movements it stands out like a sore thumb. It used to be watching Youtube videos on a Mac with Firefox would result in some extreme dropped frames but watching that same video in Chrome (especially on Windows) would result in much smoother playback (Mac Firefox has since improved, by the way). Maybe this is because of the locked 60Hz of Apple monitors playing back a 59.94Hz video? If you look at Quicktime's inspector as it plays anything back, the framerate is never consistent.

So the bottom line is that it only affects playback on the computer.

Hey Stewpid! (Don't take that personally)

I did wonder if leaving IS on in the XF-300 might contribute to the problem. I generally have it set to the "standard" setting, so I wouldn't think it would create that much of an issue. Seems like the judder occurs at syncopated/timed moments in the clips. So to follow-up, turning IS off eliminated the problem for you?

Thanks for your input...

Redifer:

Thanks for responding. I have watched so many other clips with pans shot on the same camera, that are not doing this. I watch them on the same computers/monitors. I read something about pan speeds being a factor, but I'm not doing anything where speed should be an issue. It's interesting the judder appears to occur in the same spots of these clips, regardless of source media. While I have certainly seen judder on other clips, there are so many that do have this issue. Still confused...

Well there is a quick test you could perform. Put the camera on a tripod, do a pan. Stop recording. Now turn on the IS and do the same pan again. Stop recording and import both. Notice any difference in the judder?

Redifer:

Yeah, that's what's on the agenda next.

Just going to try some things and eliminate potential causes one at a time. I'm thinking the stabilization I'm applying in FCPX may be combining with the IS setting to create the problem. You're right, though...going to start with the obvious and work from there. Thanks!...

Hi Augustheat

Yes, not using IS cured it 100% for me. And conversely, putting IS on, guaranteed judder on slow pans.