Replicating specified colour in bright sunlight

[thomas_bussey]

I know I may be wishing for something unrealistic here - put a colored surface in bright sunlight and it's going to seem... bright. But at the same time I know the client is going to say 'that's not the color we specified.

He's given me this reference. I'm on Vray 6, max '23, gamma correction on as default, screengrab below. I couldn't get my head around the vrayColor gamma settings so just picked the colour from web and with gamma=1 and srg primaries this seems to be right (I guess that's correct as max is going to do the sRGB to linear conversion anyway right?)

So in my scene I've rendered with a dome light on 15 multiplier, and checked the raw diffuse, they both look ok when compared to the original swatch. BUT: when I turn on my bright HDRI (Cosmos DAY#21) the resulting colour in the beauty gets way too bright. all reflections on that material are currently off.

Like I say this probably makes sense, but is there any way to counter it? I'm pretty happy with the exposure and lighting generally, so I don't want to go messing with that too much, should I just make my green cladding diffuse darker than it should be.

[thomas_bussey]

hmm, so this seems to be getting closer, and I guess is just the same as subtracting a bit of the lighting element from the cladding only.

edit not the same, but I can reproduce in AE. I suppose I could do it in the frame buffer too.

But in theory if the RAWlighting X Diffuse X 0.4 = roughly the right color, then just multiplying the VrayColor by 0.4 should give the same result without all the compositing. Just thinking aloud now.

[thomas_bussey]

Oh, but hey, 0.4 is quite close to 0.45, so maybe I just need inverse gamma again!?