Ok so I’m a relatively new colorist, trying to learn how to use the ACES workflow within resolve. The footage I’m working with was shot on the Sony a6400, SGamut, Slog2. However, it has been exposed to the right in order to preserve as much data as possible
My normal, non ACES workflow is to bring the footage into resolve, and add two nodes: In the first node, correct for the overexposure. In the second, use Resolve’s color space transform to convert to Rec.709, which gives me a pretty “normal” starting point that I can use to start grading.
However, just getting a balanced image is proving to be an absolute nightmare once I start working in ACES. I go into color management and set it to use ACEScct, version 1.1, with an ODT for Rec.709. Then, I right-click my clip and select Slog2 as my IDT. Great, I now have a normal-ish looking image.
The problem is, it’s overexposed, which is to be expected. However, I just can’t seem to figure out how to correct it back to “normal” without completely ruining the tonality of my image. I’ve tried fiddling with curves, color wheels, nothing seems to work. If I get the tonality of the image looking normal, everything is too dark. If I get the exposure right, the tonality is all wrong and I lose detail in my highlights.
Can someone articulate a consistent approach to correcting footage like this? I just want to get to a normal baseline I can use to start grading. It’s just so much more difficult in ACES to get the look I want
Samples attached: https://imgur.com/a/2m527Af
Exposure in scene-referred is gain applied in linear. Logically, you should simply be able to set the working gamma of a node to “linear” and then use the Gain control. However that appears not to work as expected.
You can just add two nodes at the start of your node tree, both with the Color Space Transform OFX applied. Set the
Output Gamma of the first, and the
Input Gamma of the second to
Linear, leaving everything else on
Use timeline. Then the Gain control in the first node will control exposure (and the gain wheel controls white-balance). Gain of 0.5 is a one stop pull, 0.25 is a two stop pull, etc.
Thanks! I tried that, and it does make it easier to get closer to my desired look. However, I’m still having some difficulty. I understand that since the corrections are happening to a linear file THEN getting converted to Gamma 2.4, the curves and wheels won’t behave the same as if they were corrected in 2.4 in the first place.
Using the technique you described I’m able to control the midtones and shadows much better, but I’m still having trouble with the highlights. It seems as though the highlights “stick” and resist getting pushed closer or further from the top of the scopes.
When I use the Gain control on the first node, like you suggested, then my midtones and shadows behave as I would expect them to, but my highlights stick and don’t look right. But when I use curves to try to control the highlights, I end up ruining the rest of my image.
It’s almost like ACES is pushing me toward a certain “look,” but as I understand it ACES should be neutral on such things. If I want the highlights to look a certain way, shouldn’t that be up to me?
I may be misunderstanding things here. Please let me know if I’m getting something wrong