Best Way to Color Match Sony S-Log3 to Rec.709 in DaVinci Resolve?

Hey! I've been down this road with my A7S III. The most reliable method I've found is using the Color Space Transform node (not RCM) because it gives you granular control. Here's my exact setup: On the clip's first node, add a CST and set Input Color Space to 'Sony S-Gamut3.Cine' and Input Gamma to 'S-Log3'. Then for Output Color Space select 'Rec.709' and Output Gamma select 'Gamma 2.4' (or 'Rec.709-A' if you're monitoring on an HDR display). Make sure 'Combine Input ICC and Output ICC' is unchecked, and leave the 'Chromatic Adaptation' at 'None'.

That should give you a clean base. The issue with skin tones often comes from the input gamma – if you accidentally select 'S-Log2' or 'S-Gamut3' instead of 'S-Gamut3.Cine', you'll get a green/magenta cast. Also, I never use the Sony LUTs anymore because they tend to bake in a look that's hard to correct later. With CST, you can then do your primary corrections in the same node or add a separate node for contrast and saturation. Give it a try and see if that clears up the skin tones!

I second this! CST is the way to go. But I want to add one important thing: make sure your clip's metadata is set correctly in Resolve. Sometimes when you import Sony files, Resolve doesn't automatically detect the gamma, so you have to manually right-click the clip, go to 'Input Color Space' and set it to 'S-Log3'. If it's left as 'Auto' or wrong, even the correct CST won't work.

Also, for skin tones specifically, I use the 'Color Warper' after the CST to fine-tune hue and saturation. But a trick I learned from a pro: after the CST, add a node with a 'Hue vs Sat' curve and pull down the saturation slightly in the orange/red range (around 20-30 degrees) to reduce any magenta push. That usually gives a more natural look. And don't forget to set your project's color science to 'DaVinci YRGB Color Managed' with the input color space set to 'Sony S-Gamut3.Cine / S-Log3' – that way you can use the RCM as a fallback, but I prefer manual CST for control.

Great advice so far. I'll throw in a slightly different approach that works well for me: I use the 'Sony S-Log3 to S-Gamut3.Cine' LUT (the official one) as a starting point, but only as a reference. I apply it on a node, then I adjust the contrast and saturation manually. The LUT gets you close, but I find it can clip highlights and sometimes make skin look a bit plasticky.

My actual workflow is: first node – apply the LUT, second node – do a white balance correction using the eyedropper on a neutral gray in the shot, third node – for skin tones, I use the 'Hue vs Hue' curve to shift any greenish tones toward yellow/red. That's a quick fix if you see green. Then I add a 'Gain' node for overall exposure. It's not as scientific as CST, but it's faster and I get consistent results.

One more thing: if you're shooting in S-Log3, make sure you're exposing properly – usually +1.7 to +2 stops overexposed (using zebras at 95-100% for highlights). That gives you cleaner shadows and less noise, which makes grading easier.

Thanks everyone for the detailed replies! I tried the CST method as suggested by vlogflow85, and it made a huge difference. The skin tones are now much more natural, and I can finally see the colors I intended. I also double-checked the input color space on my clips, and a few were indeed set to 'Auto' – that was causing the green cast. I also used the Hue vs Sat tip from cliphub48 to fine-tune the orange tones, and it worked like a charm.

I'm now comfortable using the CST as my primary conversion, and I'll keep directorspark50's LUT approach as a backup for quick projects. You guys are lifesavers! Thanks again for sharing your expertise – this community is awesome.