For the past few projects we have off-lined in Avid Media Composer and then did our conform in FCP7. Our sources have been HDSR tape, 1080 23.98 444 RGB with a Log source. Panavision Genesis or Arri Alexa. When doing element capture or the conform we would use the FCP7 system with a Kona3 card. Capture using the AJA Log RGB codec, full range (0-1023). Bottom line of that was pixel in = pixel out. What I digitized was a match to what was on tape. I could digitize, insert edit back to the tape, and then digitize again and it was a pixel to pixel match on the resulting digitized footage.
So I was interested in how MC6 would compare. I set up a test system running MCv6 on OSX 10.7.2 with a Kona3 card using AJA drivers v10.0.1.
I digitized a few shots in the original FCP7 system as a base line. Then on the MC6 Test system I used the AJA VTR Xchange application to capture footage. Different CPU, different Kona card, and different source SR deck then I used for the FCP 7 system, but same source tape and same section of footage. The footage matched between the two systems.
Then I launched MCv6. Made a new Avid project. 1080/23.98 RGB. I did capture test with 1:1, DNxHD, and ProRes4444. And none of them match the footage from either the FCP7 system or the test I did on the Avid system using AJA VTR Xchange. I think the problem is that the Color Space setting for the Avid project is RGB 709. The 709 part being the problem. To capture Log footage I need full range RGB capability. Rec 709 just won't do. It looked like what MC6 was doing was actually taking 64 (16) and moving it to 0 and taking 940 (235) and moving it to 1023. I think that's what's going on. At least when I start pixel probing the values and looking at histograms that's what appears to be happening. But maybe I have a setting wrong somewhere in MC6.
I'm not sure if there are plans to fix this or not. But I sure hope they do. I would really like to be able to do my element capture and conform on Media Composer.
If anyone has any observations about this they would like to share I would like to hear them.
Thank you,
Jay
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