Reflection exit color equivalent in Vray for Rhino

[Juanma Gallego]

Hello,

I was used to working with VRay for Max, but some months ago my company switched to Rhino. I've been trying to convert some materials from one platform to the other, but I have a problem. I would like to know if there's a way of getting something similar to a reflection exit color in Rhino.

I'm using Rhino 5 SR14 with vray Rhino 3.60.04

Thanks

[Peter.Chaushev]

Hello, Juanma,

The Exit Color parameter has been removed due to optimizations. It is no longer available in V-Ray Next for 3ds max as well.
Could you illustrate what is the effect you wish to achieve? Be sure to read the following discussion: https://forums.chaosgroup.com/forum/...746#post978746

Kind regards,
Peter

[Juanma Gallego]

Hello, Peter

I have a material with a difffuse and a reflection map. They are supposed to render as a slightly dark gold. When I use them I get a yellow/greenish tint that I used to avoid using a brown exit color. I was just trying to do the same in Rhino

Regards

Juanma

[Peter.Chaushev]

I assume the reflection map is not achromatic which probably gives the tint? Try using a grayscale map/color and see if the tint is gone. Alternatively, use one of the preset materials (https://docs.chaosgroup.com/display/...rials+Category) and fine-tune it to your liking.

Kind regards,
Peter

[konstantin_chaos]

Hello, Peter

I have a material with a difffuse and a reflection map. They are supposed to render as a slightly dark gold. When I use them I get a yellow/greenish tint that I used to avoid using a brown exit color. I was just trying to do the same in Rhino

Regards

Juanma

Hi Juanma Gallego,

Most often than not opposite color tints are caused by the internal energy preservation properties of the V-Ray material.

In real life Diffuse and Reflection is the same effect - the light reflected by the material.
And it is impossible for a material to reflect more light that the amount hitting the surface.

On the other hand when you work with diffuse and reflections as separate parameters (in a CG shader), you can set a material in an unnatural way - diffuse + reflection adding up to mere than '1' (meaning that the material is supposed to reflect more light than expected).
Because of that V-Ray has a built in functionality to clip the final material albedo automatically.
For highly bright and saturated colors this leads to opposite color tint to appear.

There are two things to consider here:

1) Your material should be set with balanced Diffuse and Reflection colors.
In your case you might have to decrease the Diffuse color value and possibly slightly adjust the saturation of the reflections.



2) You can change the Energy Preservation Mode for the material to avoid the tint (not natural):


Regards,
Konstantin