Is there an Iray Dermatologist in the House?
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I decided to convert a character that was using SC Joy for Genesis 3's default settings (I think) to a dual-lobe, chromatic SSS model, based on another character skin that's been very successful across many lighting conditions. Initally, I started by messing with the settings, but I started to get werid results with green SSS artifacts, so I started again, using the same material settings as the original character (figure 2 in the attached render). I swapped out the textures and lowered the saturation and boosted the luminosity of the various color channels to get the pale skin I was after. Things went weird again. I triple checked to make sure I wasn't missing textures, emission was turned on, and everything else I could think of. Then it occured to me that maybe the scene got bugged, so I loaded the other figure and rendered: it comes out fine.
I can't figure out why I'm getting this completely bizarre effect. In previous versions, it looked like the HDRI was being used as a map inside the skin shader (which it isn't). Any suggestions on fixing or trouble shooting this?
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Update. Additional testing showed that this estreme SSS with bizarre colors comes from the Chromatic SSS mode. I can't figure out why it's bugged for this character but not the other.
I went back to my usual settings for this character, tweaked it a bit and all was good. Then I turned the SSS from Mono to Chromatic and it immediately went wacky. I didn't render it out this time, but took the attached screenshot.