DrHemulen wrote:What settings are you guys using for opacity? My eyes end up with rather dull reflections or weird alien reflective eyes
i'd say: better geometry yes, maybe even uv-remapping is already sufficient - most probably.
i have also tested a modified eysurface geometry with real thickness including the lens shape, to simulate the water film, but the outcome is not worth it; octane doesn't work very well with material zones/boundaries that are only fractions of millimeters away.
on the other hand you can't go with just iris/pupil/sclera (as i thought a while back) since these will never create correct reflections.
i think the most useful recipe in terms of minimum needed modifications vs. result is sclera + cornea (like above), ideally using the exact same material; this also covers the fact that reflections are created on the outermost shell of a real eye.
what the example above is currently missing is the wet look that a real eye naturally has; but when working on the teeth material, i got real close (imo), by using a specular + sss & glossy + thinfilm material mix. imo it should be possible to use that for an eye material also.
so the only modification needed would be a different uv-set for the cornea in order to have it take the high res pupil texture instead of the full sclera (with only a low res iris).
drawback = no more control of pupil dilation - the benefit is compatibility with any existing eye texture, plus perfect reflections...