Blend material - coat as transparent layer

[LarsSonparsson]

Hello

I would like to create basic material like wood and then
add coat layer as varnish.

How do I do that in Vray?

If I try that with VrayBlend material, it will turn my material transparent.

-LarsSon

[Neilg]

I use the vray blend mat for this and it works fine, you must be doing something wrong.

Put your wood in the base material, and in the coat put a falloff in the reflection, .9 glossiness and completley refractive.
You can then play with the colour next to the first coat in blend amount.

So long as the bottom material isnt transparent, your material wont be.

[LarsSonparsson]

Nope, it doesn't work.

I just tested with really simple setup.

Teapot and in front of it is plane with blend material.
Basematerial default gray vraymtl
Coat Vraymtl
-refraction 100% white
-reflection gray
-glossiness 0.9
-Fresnell reflections IOR 1.6

With this setup I can clearly see teapot behind plane.

[chrisjacks21]

I have come across this before, any transparency to the coat material seems to affect the overall transparency of the base material, would be interesting to hear more about this...

[tct70]

Strange................I've just tested cubiclgangster's method and it works perfectly.

[vlado]

Well, you did specify you want Refraction in the coat layer, and this is what you get. If you don't want it, turn off the "Trace refractions" option for the coat material.

Best regards,
Vlado

[LarsSonparsson]

[quote=vlado;382442]Well, you did specify you want Refraction in the coat layer, and this is what you get. If you don't want it, turn off the "Trace refractions" option for the coat material.

But then coat layer wont be transparent anymore.
If I turn trace refraction off, it will be normal material
in top of another.
I'd like to have kinda glass layer in top of my base material.
So that if i change colour of coat material, it doesn't affect
anything, because it's fully transparent. So that I get reflections
from that material only.

Maxwell users understands what I'm after. ?

-LarsSon

[Codi]

Using opacity instead of refraction would do the job?

[vlado]

V-Ray is not Maxwell; I haven't used Maxwell either, so I don't know what you are after.

However, you can play with the Blend color of your coat material to give it transparency relative to the base material. You can also map the Blend color with a Falloff map to make it more transprent on the front side (so that you can see more of the base material).

Best regards,
Vlado

[LarsSonparsson]

yes I Know VRay is not Maxwell, that's why I'm using it

So how would you do wood material with varnish on top?

Basicly it has base material with wood texture. Little bit glossy
reflection. Then the varnish layer on top of that (coat). That
layer shouldn't hide anything under it. Only add some sharper reflections.

I'm just trying to create material I need...

[Neilg]

Refraction works fine in the coat layers for me? It makes the coat transparent, leaving the solid base layer there (albiet slightly darker).

[simmsimaging]

VrayBlend works more like the material layers in Maxwell, not like the coatings. Use it in the same way you would create a multi-layer mat in Maxwell and it's pretty close. I have found that same problem with the whole material becoming transparent, but not everytime and I am not sure what I did differently. Right now it works okay. Just make sure your coat layers are set to 100% reflection so the diffuse gets hidden entirely and then you don't have to use any refraction in the coating anyway. I think if you want to get that really deep/thick feel in the lacquer you may need to use geometry.

b

[Codi]

In my tests it appears transparent if the object has no thickness and opaque if I add some with a shell modifier for example.

[LarsSonparsson]

VrayBlend works more like the material layers in Maxwell, not like the coatings. Use it in the same way you would create a multi-layer mat in Maxwell and it's pretty close. I have found that same problem with the whole material becoming transparent, but not everytime and I am not sure what I did differently. Right now it works okay. Just make sure your coat layers are set to 100% reflection so the diffuse gets hidden entirely and then you don't have to use any refraction in the coating anyway. I think if you want to get that really deep/thick feel in the lacquer you may need to use geometry.

b

Yes!!! Thank you.

Off course, I have to make coat 100% reflective. Then diffuse color
doesn't effect anymore. That was my mistake.

[vlado]

I think for such a material you should not be using refraction anywhere; to change the transparency of the coat material relative to the base one, use the "Blend" texture slot for that material in the VRayBlendMtl interface (e.g. put a Falloff texture in it).

[EDIT] Ah sorry, I see you already solved it... I didn't realize you wanted to remove the diffuse portion of the coat...

Best regards,
Vlado