Sub surface Scatttering

we have a  photometric target point with ray shadows aimed at a real life sized teapot.

to capture all the photons we are inside a sphere with normals facing in. I set mine to teh defulat max gray material.

 

FG is off

we use a mental ray material

all the work we will be doing will be here in the surface shader

the photon shader is kept to the default values

Set the material color to a dark saturated color:

the scatter coefficient spinners must be tweaked to get the desired color for the areas you want to show subsurface scattering.

these are the defaults:

adjust these settings. they are based on RGB from left to right.

increase absorption to “absorb” a color

scattering is what sss is all about. decrease numbers to see in increase in the presence of a color.

as you play with these numbers they will start for give you some sense of control.

we are working with the light values of rgb and it will take some getting used to.

mental ray will make black blotches on the render if values are not acceptable.

these numbers [expecially the photons and the maximum radius] are critical to adjust by increasing them if the scattering is blotchy

This shows placing a sphere inside the teapot, with a duplicated sss material, only set to a dark red instead of dark green: