ACEScct... and maybe "s"?

colorcorrection
acescct
Tags: #<Tag:0x00007f3c681878a0> #<Tag:0x00007f3c68187760>

(Charles Boileau) #1

Hi to all,

The adding of the toe in cct made it much easier to “lift” the blacks without having them “stick to the floor”.

I was wondering if anyone is noticing that the highlights behave the same way…? It is sometime hard to “knock them down”.

Maybe there should also be a shoulder? ACESccts?

Thanks!


(Peter) #2

I would say that’s already the case. Isn’t cc and cct a quasilog function? So the highlights get compressed as we move up the scale more and more. Thats also the reason, why it’s so hard to get to a pure sRGB white.

I didn’t get what you mean that it’s hard to knock the highlights down. When you trun down gain or offset I find them to come down as expected. But maybe I didn’t exactly get the problem you describe.


(Jim Houston) #3

I suspect that it is something I have seen where some colors stick out in the highlights
for a little longer than others as you bring them down … not sure if that is the right way to put it. If that is not it, Charles, please speak up.


(Charles Boileau) #4

Hi guys,

Sorry for the radio silence. I was busy grading a movie (in ACES). :wink:

What I mean is that sometimes the highlight “stick to the ceiling”. If I have highlights that clipped or very bright ACEScct will sometimes prohibit me from making them “grey”.

This will often happen when I have a high contrast situation. Like an interior with windows etc…

When grading in YRGB in Resolve and using LUTs (etc…) you can always go “before” the LUT and use the “HL” function in resolve to “tone down” the highlights and get the available detail back into the bright area. In ACEScct sometimes that is hard to do. It’s like it’s trying to keep very bright highlights intact.

We had the same problem with the blacks ACEScc before the added the the toe. The blacks would never lift completely.

I hope I’m clear enough. Can anyone from @ACES or @acescentral comment on this. I’d be surious to know if I’m just way off with this assumption. Cause all colorists here at work feel this when grading in ACEScct.

Cheers!