Thanks for the invitation to play raw :-). I needed a break to actually try the software I’m working on. I pasted the jpg into MyPaint. I know, hardly “raw”, and MyPaint isn’t color managed yet (eek). At least I assigned my monitor profile and converted before uploading. . .
Anyway, the only interesting things I did was assign my brush color with illuminant “A” and work almost totally unsaturated to get that yellow color. I used a custom channel picker to pluck a few ciecam16 “lightness” values from the original photograph to get started, and adjusted my brush lightness with ciecam16 (JMh/JCh) adjusters that I’ve been adding. Here’s the interface so far (bottom block), somewhat inspired by GIMP’s LCH sliders. Although, I find just using the keyboard shortcuts much better for small adjustments. In retrospect I really should have used 2 layers, one for the sky and one for the clouds. . .
cHUE is just a static hue bar at lightness 50 and colorfulness/chroma 35. and cH, cS, and cV are the ciecam channels.