I'm having an issue when I attempt to downconvert an edit through compressor and add letterboxing.
The source footage is all 1920x1080 ProRes edited in a 1920x1080 ProRes timeline in FCP. I exported an HD ProRes master from FCP to bring into Compressor for downconversion since it'd make use of Optical Flow for the scaling.
When I play back the file that Compressor gives me it's apparent that the black levels on the letterboxing are not the same as what is in the video. I see that the video levels are darker on the video because there is a gradient at the end of the spot that goes to black and there is a large contrast between it and the gfx. Once I noticed it there, I also noticed it throughout.
I've tried various color space settings in Compressor (Default for encoder, Preserve and HD(709). None of these made a difference.
Since the spot had to be uploaded to DG Fastchannel ASAP I had to opt for nesting the HD sequence in an SD sequence and rely on FCP to do the scaling.
If anyone has any insight into this problem or error in my workflow please advise, as I would like to be prepared for the next time.
If you need any clarification or if screen shots or small clips would help let me know.