Jittery footage on export from Final Cut

[Jamie Baughman]

Hi Folks,

I thought about posting this in the edit section, but the issue seems to be just with the 720p 30fps HQ footage I shot yesterday on the EX1.

When I export from Final Cut and export as a quicktime movie the resulting QT is jittery...almost like I had too much coffee when operating my tripod. It also messed up all the crossfades...so when it goes into the cross fade instead of blending the two shots, it goes to black and then into the fade.

Any ideas?

How are you all exporting from Final Cut...which export setting?

Thanks in advance.

[Jamie Baughman]

Here's a link to the test footage...

And don't pay attention to the crazy WB and iris levels...this was my first test drive! Also turn the volume down so you don't have to listen to the realtor VO!

Thanks all...

http://www.westvalleyhometours.com/c...irst_floor.mov

[Craig Seeman]

I'm not sure what your exact workflow was but I'd make sure it's rendered first and then I'd export either a self contained or reference movie in the timeline's codec (XDCAM EX 720p30).

Then I'd give a quick playback test in Quicktime before encoding. You can than either encode in Quicktime or Compressor.

I'm seeing periodic black frames and it almost seems as if there's a motion issue. Given you shot progressive you need to make sure you have De-interlacing OFF when you encode otherwise strange things can happen.

[Jamie Baughman]

Thanks for the reply Craig. It's interesting...I went back and took out all the cross fades and I'm still getting those random black frames when I export.

Very strange...

One other interesting thing is that Final Cut's not exporting the entire sequence...and it's not stopping at the same place each time. It's like it just runs out of gas or something.

[Mark Kenfield]

Jamie, do you know if you had Optical Image Stabilisation on? A lot of my early test footage on the EX had a similar jitter because I'd forgotten to turn it off when I mounted the camera on my tripod.

[Jamie Baughman]

Mark,

Thanks for that tip. I'll take a look when I get home. Is OIS' default position "on?" If so, then it's on because I didn't change it.

Thanks again.

[Eric Pascarelli]

I'm thinking it's something in the export framerate vs. the timeline framerate.

In most clips I'm seeing a missing frame followed by a repeated frame. This implies no change in speed from camera to output.

In some clips (the bright shot panning to the fireplace) I'm seeing blend frames. This implies a speed change from camera to output.

Here's a theory: Footage was shot 30p and edited in a 24p timeline, but output as 30p movie. Every fifth frame is dropped going from camera to timeline and every 4th frame duplicated on output to your movie.

I am pretty sure there's a discrepancy between the timeline fps and output movie fps because the duplicate frames are synchronized on both the incoming and outgoing clips in the dissolves.

Go to sequence/settings in FCP and see what your timeline framerate is.

This is most definitely NOT an OIS thing. It's a very regular timing discrepancy that probably has nothing to do with anything in the camera and is completely occurring in FCP, though I can't be sure of the exact issue.


Edit:

Looking at the footage again, I think the timeline may be at 25fps, not 24. Every fifth frame (not every 4th) is duplicated in a consistent cadence implying a 25 - 30fps conversion happening at the output. The missing frames are more random, implying that those frames were dropped on importing them to the timeline and then moved around in the edit. Again - just a theory.

[Jamie Baughman]

Eric,

you're a gentleman and a scholar. It was as you said it was.

I do think my system is choking on the footage as well as the operator error that you pointed out. I'm just a gig of RAM so I think I'd benefit from at least an additional 3gb.

Thanks again for your help.