Fresnel reflection problem

[Crayox13]

This is probably math but I have fresnel reflection on the floor and it reflects my windows. I like it but I know client will say it's too strong, so I reduce the refl value and instead of dimming the reflection it either disappears or it reduces the angle somehow meaning it reflects a smaller portion of the window. Any ideas? I also trie using vrayblend material and under blend amount put fallof map with fresnel selected and I get the same result.

[vlado]

Try setting the cutoff threshold in the material options to 0 and see if it helps?

Best regards,
Vlado

[Crayox13]

Didn't help. Tried changing it both in base and coat mat.
So here it is. Only thing that is changed here is refl value. Small refl has 20, and normal sized bigger one has 40. Glossines 0.9 and that refl is in coat mat. It has fresnel blen map. I also tried leaving refl value at 40 and tried reducing blend value instead for the coat and the same effect appeared.

Same thing happens with a normal vray material when I click fresnel (without vrayblendmat).

[vlado]

That's weird. Can you post that part of the scene?

Best regards,
Vlado

[Crayox13]

What do you mean? The part in the red rect. Or settings?

[vlado]

Sorry, I meant the floor (and its material), the camera, the window and the lighting setup.

Best regards,
Vlado

[Crayox13]

I sent the scene to chaos. Try coat material reflection settings 10, 20, 30. The reflection on the floor will shrink instead of dim.

[Zdravko.Keremidchiev]

The effect is caused by the fall-off map set up. I'm not sure what is the math behind this, I'll do some more tests.

[Zdravko.Keremidchiev]

Turns out the culprit is the very high (0.01) Cutoff value of the glass material on the window. Set it to 0.001 and the reflection will behave as expected.

[Crayox13]

Oh! Thank you so much! I've been using the same glass and forgot to check IT, was always focused on floor where the refl was.