This thread returns at least once a year. One important thing about eyes and Poser has to do with refraction geometry. In reality, irises are pretty flat but live behind a convex lens which makes them appear convex -- degree of curvature proportional to the angle of the lens. These kinds of refraction mechanics don't exist in Poser 4, and I confess to being too lame to know to what extent they can be simulated in 5. 3D modelers for Poser usually compensate by designing concave irises (at least two designers have admitted this to me in email). And because of this, shadows fall on exactly the opposite of where they're supposed to. On top of this is the hardness of the edge between iris/cornea and white, something you won't see in real eyes because it's (relatively speaking) soft tissue, not a cuticle. Hard not to notice once you know what to look for.