glass reflections problems...

[cocolas]

I have a question about glass. When I use basic reflections (Vray mat) I get
good reflections, but the glass itself looks bad. I set the exit color to a
dark green hoping the edges would look like real glass. With normal
reflections, the edges seem to glow. If I change the reflections to fresnel,
the edge color works, but the reflections are gone. How can I get the
reflections right and the exit color to work.

here's what I'm talking about:

here's w/ out fresnel:
[img]ftp://ftp.hdrinc.com/4OMA/4cocolas/vray/problems/glass_reflect.jpg[/img]

and w/ fresnel but no correct reflections....

[img]ftp://ftp.hdrinc.com/4OMA/4cocolas/vray/problems/glass_fresnel.jpg[/img]

thanks in advance....

paul.

[twinxel]

Try to put a falloff map in the reflection slot, change it to fresnel and edit the mix curve.

And don't forget to UNCHECK the fresnel option in the material...

Hope it helps,
Joao.

[J_Bug]

I think what you're seeing in is something along the lines of internal reflections or caustics. Using Fresnel you'll only see the reflection on the away faces. What Joao said may help but it's still not going to reflect on the perpendicular and if it does then you've almost lost the Fresnel effect. You might be able to fake it with an output map for the edge faces and use a VRayWrapper so it doesn’t act like a light. What happens if you crank up the Max depth to something like 50?

--Jon

[flipside]

If you want dark edges use fog color with a very low multiplier. This will make sure that the edges are dark (because actually you're looking at a very thick glass on that edge).

For reflection I usually put a falloff map in reflection slot with perp/away and adjust the curve to get fresnell effect.