Vray RT and Cuda rendering brighter....

V-Ray V-Ray for 3ds Max General
1

Hi! I’m testing Vray RT to previz a job, the CPU version works pretty well, things looks pretty similar, but when I use the Cuda version, the scene looks a lot brighter, any clues what can cause that? is this normal?

Thanks!!!

2

Hi there,
The result from the GPU should be pretty close to the production.
Make sure that you are working with the same color space (e.q. if you use VRayVFB, check if the sRGB button in the VFB is (un)checked).
Keep in mind, that the GPU version always has GI “on” (it does not respect the on/off toggle in the VRay Indirect Illumination settings), so make sure you are comparing with GI “on”.
What kind of lights are you using ? Can you tell the VRay version and the GPU model ? Can you provide an image (or a scene) so we can take a look ?
Best,
Blago.

3

Thanks! I will take a look at what you say. I think that is somehow related to the HDR I have in the environment map I have loaded, because if in the Cuda version I turn it off, then it renders like in the CPU version… I’ll take a deeper look tomorrow and let you know.

Thanks!

4

Hi,

What is the mapping type for the HDRI that you are using ?

5

It was and HDR file and loaded with the MAX HDRbitmap map… May be I need to use Vray HDRI map?

6

Can you send us a sample scene ? We don’t need the whole one - the lighting part will be enough.

7

My guess is that in your non-GPU scene you have lowered the GI multipliers, something you can’t (yet) do in GPU rendering. Is that something you could add, Vlado? I like to lower them myself to add contrast when necessary.

8

I think the problem is that I was using Final Render HDR loader, not know it was part of FR, since does not says anything about it.

9

I suppose this is the issue, could you try to use V-Ray HDRI map instead.