DaVinci Resolve Forum
Colour change inside and outside Resolve pre-grade
Colour change inside and outside Resolve pre-grade
by Ken Evans on Nov 28, 2019 at 4:04:49 pm

I'm just delving into using Resolve to grade some clips, I've used it before but years back so I'm learning the new interface and features. However on loading in the clips (chot with an Ursa G2) I spotted they have a red cast on them. Checking back into FCPX where I'm editing and they are definitely less red. I've attached a picture, the FCPX shot is on the left, shot from Resolve on the right.

What's going on? Is it applying some LUT to the clip before I even start the grade process? (no LUT is ticked) I'm concerned it will look different when back in Final Cut. Any help would be amazing!

Media Manager - Master of Malt

Re: Colour change inside and outside Resolve pre-grade
by Brent Marginet on Nov 28, 2019 at 4:43:46 pm

This is not really all that out of the ordinary. Every piece of software uses it own proprietary code for the viewers. The viewers are essentially proxy views of the media so how each type of different code interprets and displays the proxy will be different. Part of the difference can also be how this code deals with and interprets your desktop colour space. Resolve has a setting somewhere that allows you to use the Mac Desktop Colour Space if you want but I do believe it’s best to keep it turned off.

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Re: Colour change inside and outside Resolve pre-grade
by Michael Gissing on Nov 28, 2019 at 11:33:35 pm

Export the clip out without a grade and look at it in FCPX. Is it actually different. Brent is right. If you are using the computer display and comparing the way two NLEs approximate the image, you are going to think there is a problem.

Resolve is designed to pass the correct signal via a Decklink card to a calibrated external monitor. Using the computer monitor to make a judgement is always likely to yield variable results. And who knows which one is closest to correct - FCPX or Resolve. Probably neither

Re: Colour change inside and outside Resolve pre-grade
by Ken Evans on Nov 29, 2019 at 7:54:06 am

I'll try the rendering out of Resolve back into final Cut as a test but I did discover through a colleague who's in the colour grading game that the OSX engine that processes images from Final Cut and Quick Time (and Finder preview for that matter) are not processing it 'properly' and that the Resolve image is to be trusted as a closer rendition of what is contained in the actual file, even more so if shot with a BMD camera. The gamma is also a few 'stops' up in Resolve than it is for OSX rendering and could be what is giving it a cast, as a reduction in brightness causes more saturation in the image.

This job isn't really colour critical and I'm aware these issues have always plagued Mac systems I suppose I thought after decades it would be addressed and sorted by now. I understand there's also a thing in Resolve which corrects for Mac colour rendering and the gamma difference but then it only makes it the same on just my mac and there's even differences between them as with all electronic tools. This could already be switched on since it's obviously a Mac app and hence the slightly darker, saturated image. I also understand you can insert flags into the headers of these clips so they are rendered correctly across the different apps but I've no idea how to edit them atm. Apparently these guys make an app: https://www.digitalrebellion.com/promedia/

Media Manager - Master of Malt

Re: Colour change inside and outside Resolve pre-grade
by Marc Wielage on Dec 3, 2019 at 4:27:24 am

Read these:

Grading for Mixed Delivery: Cinema, Home, and Every Screen in Between

and I think it covers the issues and the solutions very well. Understanding color management is also helpful:

Color Management for Video Editors

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