Here is the way how we can use subsurface scattering in render man.
OK let’s start
1st we take simple geometry which naturally have sub surface scattering example skin, stone, milk
I have ear.
Open Maya and load Render man plug-in for Maya
Window--->setting and preference---> plug-in manager
Open model file.
Select mesh and assign new blinn material
Now we will add Renderman attribute to blinn
Open hypershade and select blinn.
Now go attribute editor now u can see attribute option
Click on attribute option and in pop down menu we can see Renderman
Click on Renderman and click on Add subsurface scattering
Now in attribute editor scroll down and we can see Extra Renderman attributes
Now we got some extra attribute for scattering effect
Scattering Map links to the precomputed scattering pass in the passes tab of the render globals, which will be
covered later.
Scattering Strength is the amount of the effect.
Scattering Entry Tint is the color of the light once it enters the skin. This should be set to a fleshy color.
Scattering Exit Tint is the color of the light once it exits the skin. The light will be colored by the fleshy parts
under your skin, mostly blood. Paint a general color map for this attribute.
Scattering Albedo is what is under the skin. It is a good place to paint a vein map and to paint what is under the
skin. Try mapping a 3D Granite texture to the Scattering Albedo to see how it works.
Scattering Free Path is the distance in world units that the light will travel under the surface. Play with
different settings. Use the Measure Tools > Distance tool to find a good starting distance.
Scattering Filter Scale can filter to the effect if there is any banding.
This is my final output without using any SSS map.
Besides being expensive, something that people notice is that when you have SSS on the skin, you need to have
it on the eyes and teeth to get a more believable effect. This probably does not apply to what we are doing here,
but it is something to think about. You will need it on your hands so that the character looks the same all over.
Thanks for reading this. I hope it useful for you.
