Sat Aug 25, 2018 2:45 am
So after a bit of testing, we found that by simply toggling the Optimized Media Codec to another option and generating media the weird gamma shift went away. Changing the codec back to ProRes 4444 HDR and generating media performed correctly. However, as soon as we applied a node, all the optimized media went back to the crushed gamma look. So, not a solution.
We have two color rooms with, what we thought were identical system specs. However one of the rooms has a problem decoding RED using CUDA with the Titan X. The only way we can see RED footage on that computer is by either using Metal GPU or by using CUDA and setting the blend mode in the RED decode settings to "Simple". When we do this, the RED clips that were all black video, come back to life. However we were getting dropped frame errors when generating optimized media on this system and Resolve would hang on the generating media menu and the time would tick up and the progress bar would not move, forcing us to do a force quit and restart. After a few times of this, we opened the project in the other room that plays RED back without issue. The generate media worked without hanging, but the results were a weird gamma shift as you can see in the images above.
Thinking it was a corrupt project, we created a new project and imported one RED clip. This was on the system without RED issues. When we generated optimized media, it too had the bad gamma shift. Completely different project, and different RED footage. It was in this project that we toggled the codec settings and found what we thought was our solution.
It was almost like the first system infected the project, which then infected the second system when we opened it there. So that even when we created a brand new project, that too was infected. Very strange. A full shut down and restart cleared up this issue.
So after more investigation, it turns out that the system having problems with RED footage, actually had a newer OS software build, even though both systems are at 10.12.6. We had updated the OS, CUDA driver, Webdriver and Resolve all to the latest versions hoping to fix the issue, but it was not solved. Somewhere there is a conflict. Finally I decided to clone the good working system drive and install that into the problematic room. After a few networking tweaks and some other preferences everything started performing well.
So to summarize:
10.12.6 (build 16G1212) - CUDA 387.178 - WebDriver 378.05.05.25f06 - Resolve 14.3.1 = Major Conflict preventing CUDA based RED debayering.
10.12.6 (build 16G29) - CUDA 387.128 - WebDriver 378.05.05.25f01 - Resolve 14.2 = Correct RED CUDA debayering.
I hope this helps some poor soul if they ever encounter the same issue. What a pain.