Eddie Nguyen
You can grade S-Log3 by dropping Sony’s LUT on the clip and calling it done. It works, but a LUT is a fixed recipe: it clips highlights its own way and doesn’t care what you do before or after it.
The method I use is called a CST sandwich. One Color Space Transform at the start converts the camera’s log into a big working space. One at the end converts that into normal video. Everything in between, the actual grade, happens in a space where Resolve’s tools behave predictably.
Set up the project
Open Project Settings → Color Management.
- Color science: DaVinci YRGB.
- Timeline color space: Rec.709 Gamma 2.4.
- Output color space: Rec.709 Gamma 2.4.
That keeps the project itself simple. The CST nodes do the colour management by hand, so you can see every conversion in the node graph.
Node 1: the input CST
On the first node of each Sony clip, add Effects → Color Space Transform and set:
| Setting | Value |
|---|---|
| Input Color Space | Sony S-Gamut3.Cine |
| Input Gamma | Sony S-Log3 |
| Output Color Space | DaVinci Wide Gamut |
| Output Gamma | DaVinci Intermediate |
| Tone Mapping | None |
| Gamut Mapping | None |
The picture will still look flat after this node. That’s expected: it’s now in the working space, not in display space yet.
If you shot S-Gamut3 instead of S-Gamut3.Cine, change only the Input Color Space. That’s the one setting that has to match the camera.
The middle: your grade
All the real decisions go on the nodes between the two CSTs: exposure, white balance, contrast, saturation, skin, the look. Because the image is in DaVinci Wide Gamut, the HDR palette zones and the Offset wheel react the same way on every clip, whichever camera it came from.
I keep these nodes in the same order every time. The whole tree is in the node tree I start every grade with.
The last node: the output CST
Put the second CST on the Timeline node graph (switch the Clip/Timeline dropdown in the Color page), so the whole edit shares one output:
| Setting | Value |
|---|---|
| Input Color Space | DaVinci Wide Gamut |
| Input Gamma | DaVinci Intermediate |
| Output Color Space | Rec.709 |
| Output Gamma | Gamma 2.4 |
| Tone Mapping | DaVinci |
| Gamut Mapping | Saturation Compression |
Tone mapping is what rolls the bright highlights you kept in log down gently instead of clipping them hard. Saturation compression does the same for colours that are too saturated for Rec.709.
Save it
Once it works, right-click the viewer and Grab Still, or save the node tree as a PowerGrade in the Gallery. Next time, apply it to a fresh Sony clip and you start with the sandwich already built.