Vray 5 SHEEN and COAT Question

[Jay Shockey]

Hi guys, does anyone have any quick tutorials on how to use these new features? I attended the last webinar and am waiting for it to come onto youtube so I can see it again.

Thank you!

Jay

[konstantin_chaos]

Hi Jay Shockey,

Both material layers are pretty straight forward to use:

Coat:
It's most useful if you already have a material that utilizes the normal Reflection layer and you want to add additional coating on top - Carpaint, Carbon with a shiny finish, any other metallic paint with a lacquer finish.
The coat color in most cases should be set to white.
The amount determines the strength of the layer and the gloss / roughness can be used to make the reflections blurry.
The Coat Bump can be enabled in case you want a separate bump control for the coat.
In the case of the carbon for example you might want the fibers to appear bumpy while the coating to be smooth - just enable the coat bump and leave its texture slot empty.
To see examples of the Coat in action just create a Carbon material from the library or one of the Simple car paints.
Docs page on the topic - https://docs.chaosgroup.com/display/...P/Generic+Coat

Sheen:
Most useful for fabrics. Can simulate subtle reflection in an angle produced by the micro fibers covering most fabric materials.
The Color parameter determines the color of the fibers as well as the strength of the effect - brighter colors will make the effect more visible.
The Gloss determines hos spread out the effect is - lower values make the effect more spread out, higher values push the effect towards areas viewed in an angle.
The Sheen layer is used in most of the Fabric materials in the library (Fabric A..., B, C, etc.).
Docs page on the topic - https://docs.chaosgroup.com/display/.../Generic+Sheen

Hope that helps,
Konstantin

[marthamaatkamp]

Question about the sheen... in the past, the effect you describe would be achieved by adding a diffuse coat with a fresnel opacity map, allowing the user to set the ior for the specific layer. Sheen does not accept a IOR value. So how does it work behind the scenes?

[konstantin_chaos]

Hi marthamaatkamp,

The Sheen uses a different falloff logic which should generally give you more realistic effect.
The only parameter you have to worry about is the Glossiness / Roughness.
Lower Gloss values will simulate denser and more chaotic fibers making the effect stronger.
Higher Glossiness will lead to a more subtle and only visible in an angle effect.

Konstantin

[Jay Shockey]

GREAT! Thank you!!

Jay