hi i was recently doing a render where i used alpha hair & cycles engine and the hair had a bunch of dark splotches on it, do you know any fixes for this? i've done the merge by distance thing and it doesnt do much.. it looks normal in the viewport rendered view and your renders look fine so i'd really appreciate your help!
Hey! let's see if I can help with this
Unfortunately in my experience most alpha hair will do a similar thing. I find it to be less noticeable with darker hair (and luckily most of my OCs have black hair... which I should probably diversify but anyway). Even I sometimes run into this problem and can't fix it. When that happens I'll use the clone stamp tool in photoshop to get rid of it, and the smudge tool to make it look more natural.
Merging by distance is the go-to solution, but it doesn't always work. You can also subdivide the hair mesh and then I find using the "shade smooth" modifier sometimes goes a step further in cleaning it up.
Unfortunately there is no one solution, and each hair will behave differently. The best advice I can give is to default to trying the merge by distance or subdivision solutions and if those don't work, clone and smudge in your editor of choice!
I hope this helps! & if you need clarification on any of this please lmk and I'll be happy to help further if I can!