Vray: How to enable diffuse roughness?

[Anonymous]

Hi guys,

I want to render the moon with the textures nasa published.

I could set up everything very quickly.

The moon, as you know, appears very flat even though it is a sphere.

Here an example image of the real moon:

The diffuse needs to be rough for this. There is a setting, but in my vray version (latest) it is greyed out and I don´t know how to enable it. The "normal" roughness that people usually use of course has no effect on the diffuse roughness.

I can plug a map into the diffuse roughness slot, but it does nothing. Strange fact: Only the material preview inside the material editor seems to work like it should. Diffuse roughness has an effect on it.

Usually I wouldn´t care so much about diffuse roughness, but in this lighting scenario having a point light (the sun) and else pure darkness only you will notice it immediatly.

Can anyone help me?

Here a render with the moons displacement map and a diffuse color of srgb 127 127 127 (gamma 2.2) only. Specular was set to 0. "Normal" roughness and diffuse roughness was set to 100%.

As you can see the moon appears way to round.

Thanks,

Marcus

[Anonymous]

Problem solved. I was stupid. I simply have to render via CPU and not Vray GPU.

[alexandrevrancx3d]

hello,

I've the same problem, on the basic parameters, the roughness it's gray and i don't have acces to it.

Do you know how to enable the roughness parameter (0-1) into the basic parameters in GPU after 2years it's possible now?