Can't get fine control of VrayMtl reflection amount

[avenger3d]

It appears that a Reflect value nearing 0,0,0 does not allow for only a very slight amount of reflection like I'm wanting. The attached image pretty much sums it up.

Simple scene. I have a cube being lit by 2 extruded planes. There is no other lighting in the scene.
Indirect Illumination=On

Extruded planes:
Both planes have a VrayLightMtl applied--one green, one blue.

Cube:
The cube has a VrayMtl applied with a diffuse value of 15,15,15. Almost black.
Setting the Reflect color to the values shown in the attached image, has the result as shown.

What am I missing to allow for finer control of the reflection amount?

[vlado]

Make sure you also reduce the cut-off threshold in the Options section of the material. The default value will skip the calculation of very faint reflections.

Best regards,
Vlado

[avenger3d]

Hey Vlado,

Thanks for the advice. It allowed me to reduce the reflection even more. I did think it strange that the reflection disappeared when setting the value at 2,2,2 or lower. Nice to know now how the Cutoff has an effect.

However, it seems like a Reflect value of 1,1,1 should make the reflection barely perceivable, even almost invisible. How come this isn't the case?

[vlado]

Do you use any gamma correction? It will boost the colors additionally. In any case if you need to go below 1, just use a VRayColor texture to enter floating-point values.

Best regards,
Vlado

[avenger3d]

Yes, I'm using gamma correction--trying to follow a linear workflow (see settings below). So yes, the rendered image does look brighter (gamma 2.2), but when saved I set it back to 1.0, which are the versions I uploaded above. I'll admit, I'm still trying to understand the linear workflow concept.

I tried putting a VrayColor material in the Reflect map slot as you suggested, Vlado. It seemed to make changes to more than just the reflection though. So I figured out another solution... For the colored planes, under Vray object properties, I unchecked 'Visible to reflections'. Then I duplicated the planes, and for the duplicates, rechecked 'Visible to reflections', but unchecked 'Visible to GI'. Then I made a separate material for the duplicate planes that was less bright so I can use the duplicates as a reflection source only, and the original planes for GI only. It still seems like a Reflect value of 1,1,1 should allow for a barely perceptible reflection, but the solution I came up with gives me the result I want. It works for this simple scene at least--I can just imagine what a nightmare it would be to try to do something similar for a very complex scene.

Thanks for your responses, Vlado. Much appreciated!

My gamma settings:
(under Customize>Preferences>Gamma and LUT)
Enable Gamma/LUT Correction=checked
Display: Gamma=2.2
Materials and Colors: both settings checked
Bitmap Files: Input Gamma=2.2, Output Gamma=1.0