Color shift between Mercury Playback and Software Only - tied to 'max bit depth'
by Mike Kelland on Jan 13, 2017 at 2:30:03 am
I'm finding a noticeable color shift between viewing clips (of all flavours) when I switch between OpenCL and software only - green stays still in scopes but red and blue jump up noticeably. The changes seem to be linked to 'max bit depth setting' in sequence settings, which I have on while editing. The change doesn't seem to be there when you deselect 'max bit depth' - but then the exported file will have the change if you export with 'max bit depth selected'.
I grade in OpenCL as it's far more responsive. I first noticed this when I put a Red Giant wipe transition on a clip, making that part of the timeline have a red bar above it, while the clip itself has a yellow bar. As soon as you hit the transition the color changes.
I'm seeing this on many different formats and in the exported ProRes file - i.e. if I exported my timeline software only then it would have the color shift, if exported OpenCL then I'd get what I see in Programme window and on external video monitor.
Is anyone else seeing this? A quick way to test is to open RGB waveform scope, add a non accelerated effect to clip that has yellow bar above it (neutral settings) to give a red bar above clip and toggle it on and off. Then turn 'max bit depth' on in sequence settings and then toggle effect on and off.
Which is the true color? If I need to export via software only then I have to apply a rgb curve filter with tweaks to red and blue to get it match what I saw while grading in OpenCL.