Color (Aces, LUTs, Gamma etc)

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Important Links

ACES, OpenColorio, Octane, theory

The Hitchhiker's Guide to Digital Color (Sobotka)

TBR (to be read)


sRGB has the same white point as rec709 (D65), but it is gamma 2.2, whereas rec709 is gamma 2.4. P3 DCI has a warmer white point (D63) and is gamma 2.6. This is because in a theatre, it's a darker viewing environment and reflected light rather than screen light. So your eyes adjust according to the environment, and then it "looks" the same as a screen.

If you're used to sRGB and need to output that colour space, then I would keep your screen set that way. Unless you're making DCPs for a theatre, I don't really see the need for a DCI screen. All your outputs will look dark and cooler as soon as you see it on an sRGB screen.

A 2.6 EOTF (the correct term for screen gamma) is darker than a 2.4 EOTF... 2.2 is brighter. The green white point is irrelevant, as compensation is made to make sure whites remain visually D65. Actually, DCI P3 D65 is now commonly used.

Also, Rec709 is not 100nits. A grade-1 display is specified at 100 nits for grading, but Rec709 has no such specification.