/3/ - 3DCG

>>673986
Ah, you're doing what I did a couple months back.
Here are some things you should know that could help to solve your issues:
If you're using Principled Transmission / Glass BDSF on the outer eye mesh: Congrats! You've run into a fundamental flaw of the Cycles render engine. It can't render proper caustics*, meaning it casts shadows. That's likely why your eyes are so dark. You can attempt to remedy this with this method I found: https://docs.blender.org/manual/en/dev/render/cycles/optimizations/reducing_noise.html#render-cycles-reducing-noise-glass-and-transp-shadows
As for your Random Walk SSS troubles, well... it's an inherent issue with Random Walk. It's not one to do with Cycles, even Arnold users face the same issue. Whenever subsurface radius is set to red, very thin parts of your mesh will end up blue. I guess it's got to do with how RGB light transmits under the Random Walk algorithm. (red penetrates the furthest, blue penetrates the least?)
I guess I should post how far I got before I realised learning to make this shit from scratch would be more satisfying and fun than toying with Daz. I never perfected the shading of the eyes, and if you zoom in to the eye you'll notice the Random Walk blue tint on the lacrimals and eyelids.

* - it can, but it requires so much computation that it isn't efficient. You can attempt bruteforcing caustics rendering by bumping up Transmission sampling, but it'll always stay noisy even set in the tens of thousands.