So you think there should be a second Rec 2020 preset with input gamma 2.4? Is that the linearised gamma function like the current preset?

Yes A second rec2020 preset with a gamma 2.4 should be even better !!
It's the same gamma as the BT 1886 : 2.4
Thanks again

Isn't the current gamma correction defined as part of Rec 2020? How can it be Rec 2020 if it has a different gamma? Perhaps I misunderstand.

I'm no expert but what i understand is that :
in resolve there is 2 différents color space and gamma for Rec2020

• Rec2020
  -Rec2020 gamma 2.4
  If I use the first color space/gamma for my dpx then I load them in dcp-o-matic with the new rec2020 preset, it fine
  But if I use the second color space/gamma, with the same new preset it is not good.

When I chose edit in the colorspace menu, It shows that rec2020 preset hasn't got a 2.4 gamma ... or i misunderstand something !!:-)

Ok I dig further:
Rec709 has a gamma similar to 2,35 but it's for HD Cameras
BT 1886 has a true gamma of 2,4 it's for HD Monitor and distribution
Rec2020 has a true gamma 2,4 it's for UHD Monitor and distribution

So in DCP-o-Matic 2.9
The gamma of Rec2020 preset isn't correct
Rec709 should be labeled "Rec709 Gamma 2,2"
May be add Rec 709 preset with a gamma with a linear start
I'm clear enough ?
Thanks in advance

Hi Olivier,

Thanks for your notes. I've changed the Rec2020 gamma to 2.4 in my local copy.

Do you have any references for the use of a Rec 709 preset with linearised gamma?

I'll have a think about renaming the existing Rec 709 preset. I'm tempted to leave it as-is to avoid confusions...

Thanks,
Carl

I believe this is all ok now; please leave a note if not. I'd like to see some reference to use of Rec.709 with linearised gamma before I add a preset for it. Thanks!