Couple of things I've found on lips..... 1) If the lips are /slightly/ appart, make the gums and teeth transparent. That stops any rendering artifacts appearing. See my Agghhh image for a bad example of this. 2) Create a transmap for the lips (use the head bumpmap as the base). Make the lips white, and everything else black. Play around with fluzzying the border b/n black and white. Use this transmap as a mask for glossiness (or ansiotopic) specularity. To do this, plug the transmap into the spec colour of the glossiness node, and plug the glossiness node into the alt spec slot. There are a few examples of this around, and the result is outstanding. See my "Something on her mind" gallery image for a close-up.

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Creator of OctaneRender for Poser
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