Strange reflection glossiness element from vrayBlentMtl

[re:FORM]

I don't know if this is expected behaviour or not, and I don't remember coming across this issue in 3dsmax, but when I have a blend material, my glossiness render element does not give the result I would expect. If I have a material with 0.8 glossiness as coat on a non reflective material, blended at 50%, I would expect the glossiness to remain at 0.8... but the result appears to have been darkened. Reflection filter I would expect to be darkened, but not the glossiness value.
Any ideas? Am I losing it in my old age?

[vlado]

The glossiness element is blended like all others. However this element only makes sense if you are using plain VRayMtl materials; it's anyone's guess what's supposed to happen with multiple blended materials.

Best regards,
Vlado

[re:FORM]

Aha, that is true. That was a bit of a stupid question wasn't it. I just assumed Vray might have done some interesting maths to give a sensible result....
Bizarely, I'm now using a single vrayMtl but for some reason the vrayReflectionGlossiness RE still doesn't match the extraTex RE; it appears brighter (gamma?). I assume it's a color mapping issue. Would it be possible that the extraText have a gamma correction applied and the straight vrayReflectionGlossiness not?

[vlado]

If you are saving to an 8-bit file format, then the image will be gamma-corrected, yes - depending on the 3ds Max output gamma settings.

Best regards,
Vlado

[re:FORM]

This was just from viewing in the VFB.

[vlado]

Ah ok. The VFB adds sRGB color correction to almost all elements; it doesn't know that the glossiness one shouldn't have it.

Best regards,
Vlado