Light Select and Environment Volume

[TheScope]

Hi,
I noticed that Light Select render elements do not contain any environment volume effects, only the final render does. Not sure if this is a bug or a feature but I guess it would be good to mention it in the docs.

I think the best behaviour would be to be if the environment volume would be part of each light select element. Or even better, if I could get one Atmospheric Effect render element per Light Select render element.

Cheers, Florian

[vlado]

This should actually work fine. Can you post an example where it doesn't?

Best regards,
Vlado

[TheScope]

Sure.
Here is a Maya scene with some dummy objects, a sun, a sky and an aerial perspective volumetric. The aerial perspective shows up in the final render and in the atmospheric effects render element but not in the two light select render elements.

Maya 2017 Update 4
Vray 3.60.02

Cheers, Florian

[yolov]

Looking into this, I think it's actually doing what it's been designed to render, correct me if I'm wrong, of course.
The light select contains the lighting information, darkened by what the fog removes from the image and minus the actual fog color (the fog dims what can be seen through it).
Which means that beauty=(lightSel1+lightSel2+lightSelN)+atmosphere, while beauty-atmosphere=(lightSel1+lightSel2+lightSelN) where in both cases removing the atmosphere and its color from the equation yields the lighting and all its components being dimmed or darkened by what the fog makes less transparent in the final image by ... well, being fog.
What result are you expecting to get in this case? Maybe that will help us figure out if there's something that needs fixing.

[TheScope]

Hi Alex,
I think that works as long as you just add the lightSel and the atmosphere in post. Once you start making changes to the lightSel, the atmosphere pass will be wrong (e.g. disabling one lightSel that produces god rays will still leave the god rays in the image since they are in the atmosphere pass).

One solution would be to have the atmosphere in the lightSel so that lightSel1 + lightSelN = finalRender. Better would be to have one atmosphere pass per lightSel pass.

[yolov]

Ah, yes, that's correct. It won't be the same in this case. I'll check in with the devs.