Switching to vray LWF from MAXes

[Crayox13]

Hi guys,
After I learned that "don't affect colors" affects all settings and not just gamma, I had to turn it off since I had burn value set. So my gamma was set in MAX options. Now my scene has low details and noise where it shouldn't, since in vray color, gamma is now 1 so I don't get double correction.

What should I switch now to only use vray gamma? I should put those MAX settings back to 1? Won't that affect my materials - actually not affect?

In vray, should I just click LWF or set gamma also?

thanks

[plastic_]

are you using the srgb button in the vray vfb?

[Crayox13]

Yes, but I always save in *.exr so gamma is always saved in my file.

[plastic_]

then you can just set the vray gamma to 2.2 and turn off the srgb button.

you can then set the max output gamma to 1.0.

the drawback is that duplicating the vray vfb no longer works (bleached out colors in the copy), but it's better for shadow noise.

[Crayox13]

I don't use duplicating. What does it do? I mean what do you use it for?

Do I leave in MAX the input gamma on 2.2, and those "enable gamma/LUT correction", and also "load enable state with MAX files" checked?

Also those two option in materials and colors are checked now.

Also, what do I do with that new "Linear workflow" option that vray has?

[plastic_]

well i like to use the duplicate button, for comparing renders, etc.

your settings sound right.

the "linear workflow" checkbox...i don't like it. it's misleading.

apparently it's only good if you want to load & render old files. since max will only gamma-correct bitmaps, the color values in the material editor will be off, with linear gamma workflow. when the checkbox is active, all color valued are corrected to the current vray gamma setting.

for new scenes it is better to use the right color values in the first place and ignore the checkbox.

[Crayox13]

I see. Thanks for all your help.

Only one thing, those MAX settings under Gamma and LUT, what do you have set? I have all 4 checked, input gamma 2.2, output 1.0.

Also, under display I have gamma checked and set to 2.2

Does that sound right?

[plastic_]

yeah, that should be fine...

[Crayox13]

A problem. Just finished rendering a batch of 3 scenes. srgb was off in VFB, gamma was only set in vray color mapping, and scenes looked ok in MAX but when I opened them in PS they were over bright, like double corrected. I saved them in exr. Why did that happen?

[rivoli]

gamma was only set in vray color mapping

exr is a linear format, and so it will be handled when you open it in ps. if you gamma correct it when rendering, then it will be double corrected. which is not really a problem though, being it a full float file, you can easily correct the gamma in post.
to avoid exrs to be double corrected, just tick "don't affect colours" in colour mapping. vray will know that you're rendering with a gamma curve, and will do the appropriate sampling, but won't burn the gamma into the output image.

[Crayox13]

I can't click don't affect colors because I'm using a burn value also, to reduce sun intensity on direct surfaces. It seams that this option should really be changed so it only affects gamma.

[rivoli]

yep, just read the first post of the thread. then I guess you'll have to correct the gamma back in ps.