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Prores HQ export problem – beginning and end of each clip
when doing a final export from FCP, on my final movie I get subtle surges in luminance corresponding with the last two frames of each clip on the timeline.
Most of these clips have no filters or motion adjustments at all, since the sequence is a final conform or re-imported, color-timed TIFF sequences from the post house.
Any advice would be much appreciated, I’ve spent several hours scanning the forums with no success.
Quicktime Movie Export Settings: Current
Timeline Settings same as footage:
Apple Proress 422 (HQ), Quality 100%
1920×1080, Aspect Ratio HDTV 1080i, (16:9)
Pixel Aspect Ratio: Square
Field Dominance: None
FPS: 25Macbook Pro 2.5 Ghz Intel Core 2 Duo
2 GB 667 MHz DDR2 SDRAM
OSX 10.5.7 -
4 Replies
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Does FCP do this, or is it visible in the files you got?
In case of the latter, the post house screwed things up.
(Some color correctors can’t work frame accurate (Pogle comes to mind), or an EDL was shifted.If the TIFFs are fine, i have no idea…
Bouke
https://www.videotoolshed.com/
smart tools for video pro’s -
TIFFs are fine, and the Prores HQ that I converted it to plays back fine in the timeline.
On closer inspection, the luminance surges are only visible when I play back the exported movie in Quicktime. If I open the same file in FCP, the problems don’t appear in playback. But this doesn’t make the issue any less worrisome.
I wonder if it’s a coincidence that the surges happen 2 frames prior to the end of each clip though, just when the white corner-angle appears, on the lower-left corner of the screen, representing the clip end.
Thans for the help,
BenMacbook Pro 2.5 Ghz Intel Core 2 Duo
2 GB 667 MHz DDR2 SDRAM
OSX 10.5.7 -
[Ben Gordon] “I wonder if it’s a coincidence that the surges happen 2 frames prior to the end of each clip though, just when the white corner-angle appears, on the lower-left corner of the screen, representing the clip end. “
Nope
it is an computational error in the conversion algorithm when going from RGB(tiffs) to YUV(ProRes) in versions of FCP prior to v7
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflow for the Digitally Inclined
Chicago, IL -
Thanks for your input, but I successfully converted all the TIFFs to Prores PRIOR to importing and working on them in the Prores timeline. Now I’m exporting the Prores material from that same timeline to a Prores movie, so the conversion is in the past.
In my ignorance, from what I can make out, it’s some kind of frame-specific artifact embedded in the final movie that Quicktime Pro misreads. When the movie is opened in FCP it plays back fine – strange since QT Pro is FCP’s platform, right?
I tried to convert a sample of the luminance surge to H264 to post on this site but the conversion (in QT Pro) did away with the problem entirely. Hmm.
B
Macbook Pro 2.5 Ghz Intel Core 2 Duo
2 GB 667 MHz DDR2 SDRAM
OSX 10.5.7
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