Gamma shift and desaturation on export, even after adjusting renderer/bit depth

[JD318]

I've got colored clips for a feature coming out of Resolve at ProRes 422HQ. My editor brought them all into the timeline and upon export again to ProRes 422HQ again as a master file for the film I noticed a brighter gamma shift and desaturation. 

This is not a result of different monitoring equipment or software, as I confirmed the shift by importing the film back into Premiere and Resolve both and comparing the colored clip from Resolve vs. the full export of the film out of Premiere, please see attached with the premiere-exported still on left and source color clip on right.

After reading about it a bit I thought it might have to do with settings on exporting re: whether software renderer or GPU renderer are used, and whether or not "maximum bit depth" is enabled. We tried basically every combination of renderer/maximum bit depth enabled or not/8bpc or 16bpc combination there is and the result is still the same.

Is there any possible explanation or solution for this? I understand why there might be a shift in something like an H264 export, but I would not expect going from PR422HQ to PR422HQ should produce a shift, as the image is identical when doing a similar transcode in Resolve instead. Please help!

[JD318]

Forgot to mention this is OS X Catalina 10.15.4 running Premiere 15.1.0 (Build 48).

[R Neil Haugen]

Color management is a bit of a morass or rabbit hole. But ... it's one I'm pretty comfortable in.

From your comments, you exported out from Premiere in ProRes422HQ. You then re-imported that file into PrPro, placed it on a sequence, and it was different than the image on the original sequence.

Is that a full and accurate summation?

I wanted to make sure, because PrPro is hard-coded to be on systems with full broadcast spec Rec.709. A lot of computer systems aren't completely setup right, and well ... Apple chose to mis-apply Rec.709 blowing off two required sections of that standard so outside PrPro on a Mac things are dicey.

So to get started, what's your OS, what calibration have you done to the monitor, and do you have the display color management option checked on or off in Preferences?

Edit: you just updated that it is a Mac system ... so I'm re-asking, is that comparison on a timeline within Premiere ...

Neil

[JD318]

Thanks for the quick response Neil. To be more accurate, this is the pipeline:

Export colored clips out of Resolve as ProRes 422HQ > Import colored clips into Premiere timeline (OS X Catalina 10.15.4 running Premiere 15.1.0 (Build 48).) > Export full film > Bring the full film back into Resolve to compare the Premiere exported ProRes to the original colored ProRes clip – this is what the attached screenshot is. I personally do not have Premiere on my system but my editor did the same, bringing back the exported clip into premiere and confirmed the same difference in the Premiere viewer.

We are a very low budget/DIY production so unfortunately we are just doing things on uncalibrated monitors. However, would that even be relevant, as the difference in footage is readily apparent when both the source and export are being viewed alongside in the same software? As in, it seems that the process of bringing the export back into the same viewer as the source clip would confirm any difference regardless of what the display is? Please correct me if I'm wrong.

[R Neil Haugen]

Yea, these things can be fun to track down ... not. There can be oh, a couple hundred questions at times. Yea, I do go through this with a number of colorists all the time ... I'm a contributing author over at MixingLight.com my "beat" being coloring in Premiere for Resolve/Filmlight based colorists.

So the editor viewed the clips inside Premiere and they differed ... ok. Is the editor on a Mac? Do they have the display color management checked on or not in Premiere's preferences?

When the clips were exported from Resolve ... was this with standard Rec.709 or the Rec.709-A "Apple" setting?

What's the color management setup in Resolve?

Neil

[JD318]

My editor did not have display color management checked on (on a Retina iMac), but I am doing the bulk of comparisons on the clips myself on my non-retina iMac and Sony TV.

My Resolve settings are using standard Rec.709, "A" is not an available option on my version.

[R Neil Haugen]

For anyone working within PrPro on a Mac Retina monitor, like your editor is, they really should have the "display color management" option turned on in the Preferences. That way PrPro will look at the ICC profile, note that it's not a full Rec.709 system, and adapt the image accordingly to try and remap it to Rec.709 within the Mac OS/monitor setup.

I downloaded your image, brought it into PrPro on a new timeline, and checked the scopes for the two. The left image is very slightly brighter overall, and also slighly desaturated. Only small amounts of both, but still ... you do want consistency "in-house". Confirmed they are NOT the indentical images.

After matching them in Lumetri, I then exported to ProRes422HQ, Max Depth/16-bpc on, reimported, and the images I exported brought back, were identical to the images on the sequence. So I was able to export these and get a correct ProRes out & back.

I also tried another sequence, exporting/reimporting the same, and got identical images.

So ... trying to puzzle still why the ProRes on your systems isn't working correctly. It's very close, but ... ain't spot on. Should be.

Neil

[Andy 1968]

Davinic Resolve and the iMac might be to the ones to blame. The video will explain why. That being said there are things that need to be setup correct in Resolve for exporting to Premiere Pro. 

[R Neil Haugen]

So from watching Andy's referenced vid, there's a setting in Resolve on Mac's to use Mac-specific viewer options or something, which the Resolve support staff told the vid creator was needed for proper viewing on a Mac screen. Not a Mac person, didn't know about that. I'm sure it's in their massive manual.

Neil