HDR/EDR output from OCIO config being clamped before display.

[alexfry]

Hey Team

I'm trying to use the HDR/EDR preview on an Apple  Pro Display XDR in conjunction with a modified version of the ACES 1.2 OCIO config.

I have a fork of the ACES 1.2 config with a new “DisplayP3 extended (1000 nits)” display space defined here:
https://github.com/alexfry/OpenColorIO-Configs
(If you don’t want to download the entire thing, all you need is ‘config.ocio’ and ‘luts/srgbf.spi1d’ and patch it into a canonical ACES 1.2 config)

This config behaves as expected in Nuke with it's EDR mode enabled, displaying extended highlight information as expected.

But in Affinity Photo the output is being clipped at 1.0.

It seems to me that the post OCIO buffer (which contains values above 1.0) is getting clamped somewhere before display.

Both "ICC Display Transform" and "Unmanaged" are displaying extended highlight information as expected, but obviously without the OCIO defined display transform.

 

[Chris B]

Hey alexfry,

I'm going to try and find out a bit more info and I've spoke with our Photo Expert about this and he will also do some poking.

When I get any feedback I will be sure to let you know - thanks for raising this.

[alexfry]

Sounds good, let me know if there is anything else I can do on my end.
I'm sure it's just a Clamp() in the wrong spot somewhere.

[Chris B]

Hey @alexfry - an issue has been identified and the developers have fixed it. Please keep your eye on the beta forum or follow Andy Somerfield for the announcement of the beta. I'll also try to give you a nudge when I see it in a patch note  Thank you very much. 

[alexfry]

Brilliant! Thanks Chris!