Hasta La Motion!

So I’m using Maya/mental ray for an animation of a surgery involving the trachea. I’m using the misss_fast_simple_maya material and it works perfectly fine until I apply it to a cylindrical extruded surface (like a hallow pipe). You’ll see in the images that some of the objects will work, but when I apply it to the trachea (which is hallowed out so you can go inside it), I lose all backscattering effects. I tried adjusting the radius, but that didn’t seem to help. Any ideas of what can fix this? Thanks!

SSS_)1.jpg: Left object (the trachea) has the same SSS material attached as the two objects to the right of it

SSS_02.jpg: Same material (just tried a different bump to see if that was the problem). Non extruded cylinder works fine, extruded shows same problem as the last image