DistantWorlds....

The attached render is an example (taken from Costello in my gallery). Unfortantly the node setup is pretty experimental, so I can't really post it at the moment - and it wouldn't make sense if I did. But in summary....Eyeball and cornea handle all spec (turn off spec on iris and pupil). Use Anisotopic for spec at about 0.05 highlight size (smaller if you use bigger bumps). Eyeball has a spots bump - find a good eye reference shot and experiment with the spots node until you get the right bumpiness. The experimental stuff is getting the subsurface scattering into the eyeball, which is working well in this shot. And also getting the nice eyelid shadows which is done using some ugly maths that you don't what to see.
One of the challenges with all this is that specular reflects a point light. But in reality the light reflecting of our eyes comes from larger objects (windows, walls, tv's, big lights etc). So you don't want pin-point light reflections in the eyes - they have to be sharp (since the eye is wet), but also big. That's why I go anisoptopic with a large highlight and add a bump. A better option would be to have lit object in the scene to provide reflections for the eyeball. I've been experimenting with having an ambient image pasted to a skydome - to provide things to reflect in the eyeballs. Haven't got anything to show yet.

Creator of PoserPhysics
Creator of OctaneRender for Poser
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