backscatter on SSS2 skin shader?

[sharktacos]

I'm comparing the skin shaders in vray and mental ray, and am having a hard time creating the backscatter on the ear (see above). As you can see, I'm getting a trasclucent skin color (as if the head was ivory), and not the blood-red color I would expect to see there.

Comparing the shaders two we have:
MR Fast Skin Maya / Vray SSS2
diffuse / diffuse
epidermal / sub-surface
subdermal / scatter
backscatter / ***

So while in MR there is a parameter for the backscatter, there is no equivalent in the vray SSS2 shader. Given that, how would I get the vray shader to produce similar results on the ear?

Let me add that increasing the prepass rate does seem to improve this, but I am still not getting the red back scatter I would like to see.

[MoonDoggie]

Based on the Scale parameter and "Scatter Radius" in the SSS2 shader. Make it larger.

[sharktacos]

Based on the Scale parameter and "Scatter Radius" in the SSS2 shader. Make it larger.

Thanks, that's was a good tip. Actually tho, what worked was making the scale smaller. Here's a comparison again (all with a prepass of 1):


I do wish that in a future version that we could have individual "artistic" control over the back scatter and subsurface effects like in the MR shader.
In particular here, I would like to have the terminator on the face be more orange, while the back scatter on the ear would be crimson. I can of course achieve this with maps now, but having that added control would be nice.

[MoonDoggie]

Best way to do it is with the scatter radius, don't get too much scatter on a face, it's a simple mistake to make and it looks like they're made of wax. There's a couple threads on the forums about SSS2 shader that people have done (myself included). You can control the backscatter color by changing "Sub Surface Color" and "Scatter Color".

[sharktacos]

Best way to do it is with the scatter radius, don't get too much scatter on a face, it's a simple mistake to make and it looks like they're made of wax. There's a couple threads on the forums about SSS2 shader that people have done (myself included). You can control the backscatter color by changing "Sub Surface Color" and "Scatter Color".

Right, I get all that. What I am saying is that the way the shader is designed it is not possible to change the scale/scatter radius of the back scatter without simultaniously changing the scale/scatter radius of everything else. Likewise, the color of the back scatter cannot be controlled independently of the overall subsurface color. I miss that flexibility, and would prefer to be able to have the option of tweaking them independently if desired.

[JeffG2]

Couldn't you map it?

[Morbid Angel]

Couldn't you map it?

yes exactly. You can paint a scatter radius map.