Quote - I turned the gloss of the hair way down from the default that Reality had set.  I let it render for 40 hours.  My question is, even after all this time, there are still red speckles in the shadow area of the hair.  How can I get rid of that?

In theory these will clear up "eventually". That eventuality is too far away for me, so I have to resort to post work to remove them. I don't like doing this, as, unless there are only a few isolated specks, it's very hard, and in some cases impossible, to do it without it being detectable.

I believe this to be a particular problem when transparency is used. It's exacerbated by red/gold colours (if you changed the hair to a darker colour, I believe you will not have the problem—but of course, this is not an acceptable solution artistically). I only get this problem with red/blonde hair (with transparency) and high polish metals (e.g. jewellery) next to the skin—it's worse with gold. Nothing to do with trans maps in the case of metals, though, and there's a comprehensible reason for it; it also tends to clear up, whereas the hair problem never seems to—it seems like an asymptotic process.