Mental Ray - Shaders


#4721

how to use mr ocean shader,I assign it to a plane and render it , I got nothing ,only a dark plane!


#4722

Will need a lot more information than that to resolve the problem.

It could be any number of things like:

  1. You haven’t assigned an environment therefore the reflective water has only the default black environment to reflect which produces a black render.
  2. You’ve assigned the ocean(lume) shader to the displacement map but left the bump option enabled on the ocean(lume) settings so it won’t work as a displacement map.
  3. You’re using the ocean(lume) shader as a bump map but have no lights in the scene therefore this (or any) bump effect would be difficult to see
  4. You’re using photographic exposure control and it’s configured incorrectly thus causing a black render.

ETC. As you can tell, lot’s of things could be wrong with the scene so it’s a guessing game until you provide more detailed info on your scene & settings.

If you think it’s because of your material configuration you could try the A&D water preset or some of the ProMaterial water presets as they have the ocean(lume) options already configured and/or built-in.


#4723

with your help I have resolved the problem,thanks


#4724

I am looking for a easy fabric material setting. I found some very complex ones on mrmaterials.


#4725

You may need to narrow that down a bit as there’s many different types of fabrics like satin, denim, flannel, etc., and they all can be configured differently.


#4726

I want to set a basic fabric material for the seat on this scene. The original Vray scene render it so nicelly with a smooth falloff light .

Mine is done with a Arch&Design with a very low reflection glossiness value and a high diffuse roughness. But the light falloff is not strong enough to me.


#4727

Hi,

I was wondering how do you guys deal with texture maps that needs to have a higher or lower value than the standard 16 bits zero to one range while still using 16 bits images. In some materials you need to use values that exceed from far this range. By example I want to map the back scatter depth shader of an sss fast material where I want my highest value to be 120 cm. Therefore my highest value on the texture map will need to be 120 too.

How do you deal with that? I can play with the output tab (i’m using 3ds max) to boost the whites to this value but doesn’t that messes the darker values? I’m kind of confused with this issue.

I’d be interested to know hoe to do that in Softimage too!


#4728

Hi, been using mental ray for about 3 weeks now, this new rendering ideology is just starting to sink in. So far so good.
I just have a problem with a matte/shadow workflow. My scene has an object using an Arch+Design material with displacement. How do I turn this material into a matte/shadow material whilst retaining the displacement? The Matte/Shadow/Reflection (mi) material doesn’t seem to have an option to add displacement maps into it. (In vray, I would just go the the object properties and set it to matte.)

Thanks,
Jeff


#4729

You can use “material to shader” in “mentalray” material surface map slot.

I havn’t checked it myself though if matte/shadow works in “material to shader” map.


#4730

Thanks Jigu! that worked perfectly!
“Matte/Shadow/Reflection (mi)” inside a “Material to Shader” for the “Surface” of the mentalray material + a displacement map on the “Displacement” slot of the mr material (I also adjusted the Output Amount to match the strength from the Arch+Design displacement strength).
Now I wish that there was a more straight forward way of doing this, without creating multiple materials just to get a “Matte/Shadow” version. :smiley:


#4731

Heya,

  Just wanted to post the SSS article I finished recently: [mental ray sss subsurface scattering tutorial](http://www.mrbluesummers.com/3510/3d-tutorials/3dsmax-mental-ray-sub-surface-scattering-guide/).  We explore all of the parameters in the 3d Studio Max implementation of mental ray using gradient ramps and rainbow maps.  It's kinda neat.  :)
 [[img]http://mrbluesummers.com/wp-content/uploads/2010/07/mental-ray-parti-volume-original-300x180.jpg[/img]](http://www.mrbluesummers.com/3510/3d-tutorials/3dsmax-mental-ray-sub-surface-scattering-guide/)
 
 [[img]http://mrbluesummers.com/wp-content/uploads/2010/07/sss-fast-material-front-surface-scatter-color-300x180.jpg[/img]](http://www.mrbluesummers.com/3510/3d-tutorials/3dsmax-mental-ray-sub-surface-scattering-guide/)
  
  Here's a quick outline...
  [[b][u]part 1[/u][/b]](http://www.mrbluesummers.com/3510/3d-tutorials/3dsmax-mental-ray-sub-surface-scattering-guide/) covers:

[ul]
[li]What is Sub-Surface Scattering,[/li][li]The Fast SSS Material Type, and[/li][li]The Fast SSS Skin Material.[/li][/ul] part 2 covers:

[ul]
[li] The SSS Physical Material & Shader, and[/li][li] The The Parti-Volume Shader.[/li][/ul]Enjoy! Let me know if you have any suggestions or notice typos.


#4732

Mr-BlueSummers, you is the men! This is the best guide that I already see about the Sub Surface Scatering.
:applause: :applause: :applause:


#4733

Hi Mr-BlueSummers,
I really like your sss guide. I’ve read the mental ray guide and I must say that your’s is very well explained. It resumes perfectly the book but yours have a lot more renders and useful tips!

Thx


#4734

I’m searching for a way to use a mr Physical Sky, or any HDRI as an environmental reflection in the A&D shader and not in Max’s env map slot. What I really need is to render the background as black for compositing reasons.

Obviously when I turn off the Env Map slot and render black, I can’t use the sky reflection in my car paint shaders and things like that.

In the A&D shaders I’m trying to tweak fade to end color with the sky map. Is there a better way to do it?

Thanks for any help I can get.

-John


#4735

Environment/background switcher?


#4736

Thanks Jeff! Why didn’t I think of that!? Results:


#4737

hi guys, is it possible to use ambiant occlusion with the sub surface scatter shader of MR? i know vray can, A&D can, but SSS?


#4738

If I understand the question, yes you can use, just put the AO shader in the channel of “diffuse color” and “epidermal scatter color”. “Subdermal” and “back surface” does not show significant changes in the outcome.
But it will leave the render slower. It is best to separate “renders” and compose in post production.

In this video tutorial you can see what is the best way to compose the AO shader with SSS shader in post production:

http://www.youtube.com/watch?v=cyPUVjaM6Qo

:thumbsup:


#4739

FWIW Zap’s skin + material has ambient occlusion controls built-in.


#4740

Talk about over kill with AO.
Just use it in your overall diffuse color, its suffice for my renders :slight_smile: