That's interesting... her teeth aren't "transparent", just darker, but that does make a difference... here's a before and after closeup of her mouth in this scene... before...
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And after I tried your suggestion... WOW... what a difference! Your idea turns off SSS (Subsurface Scattering, which I presume has to do with scattering the light reflected off the teeth, making them appear darker? Just a guess, I don't know much about SSS but I should learn). Anyhow... great tip! Thanks! (I wonder if something similar would help with dark eyes? Adjust SSS? hmmm)...
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