Black blotches rendered on character head after applying hair

Richter-3D

Hi,  I have rendered a Genesis 8.1 female figure and before I put hair on her, she wore a helmet (a sorely big problem in Daz that you can't flatten hair for helment and hats which is another issue altogether).  So after I added about 14 other figures in my scene, I put hair on the female figure once she took the helmet off and after rendering black blotches showed up on the head.  

They usually show up on the forehead, but at other times, on the temple of the head of the figure.

I had this problem before about 3 years ago, and I can't find my notes on how to fix it.  From foggy memory, one setting in surfaces had to be tweeked a little to make the hair stand out more to get rid of the blotches.  I don't think I had to modify the figure head surface, but I'm not possitive on that one.  I've tried a few surface changes on the hair, but the hair still causes blotches.

I tried the base figure without hair and there are no blotches.

The pictures are of the same G 8.1 figure MSO vix for 8.1 females and the hair are two different ones (obviousely) Dalilah Hair for G8F and Julia Curly Locks Hair.

I included the base figure also to show that there are no blotches on her there.  Only after either hair is added do I render and see the black blotches.Before the render nothing show up as being bad.  It only effects the render.

Appreciate any help on this one.

Thanks!

Richter-3D

Richter-3D

Technically the hair says "Delilah Hair for Genesis 8 and 8.1 Female and Julia Curly Locks for Genesis 8 and 8.1 Females.

crosswind

as well as the eyes with black sclera... Because your character is far from the World Center ( XYZ 0,0,0 ), instances of geometry of hair cap / cornea and sclera caused the problem. You may check the values of XZ axis of her...

Solution: Go to Render Settings pane, change "Instancing Optimization" to Memory or Speed.

Richard Haseltine

But set it back to Memory if you are using any instances in the scene.

Richter-3D

I tried memory and speed both with no changes.

crosswind

If so, your case might be one of those "unique cases" . You may group all items in the scene, translate it to a proper position near the world center.

Richter-3D

I created a whole new scene from scratch.  I put MSO vix in and a camera.  She is at world center zero.  I put Dalilah hair on her and kept the Memory setting for Instancing Optimization.  I rendered it and still has marks on her forhead.

See photo.

crosswind

I don't have this character but I don't think the issue results from her head morph. But you may try to zero the head morph to see if there's any improvement. Or, tweak some morphs on the hair a bit.

Richter-3D

Hi, all.  I found the problem, which may be two-fold.  Both hair vendors claim they are both for G8 and G8.1 females.  When I tried a G8 figure, instead of my G8.1 figure, both hair products worked perfectly.

So, I thought, okay maybe the G8.1 female head is slightly larger in the head than the G8 female head.

SOLUTION: I changed the scale of the hair from 100% to 101% and the black blotches disappeared!

I will do more testing, but that seemed to work great.

This is one solution I have made notes on for myself for sure this time.

Thanks everyone for trying to help me.

Richter

crosswind

There's no such a difference in b/t 8.0 and 8.1. And lots of people never experience such the issue but some do see. I even could not reproduce it ~~.

Anyway ~ changing head scale is technically doable as long as it satisfies you.

Richter-3D

I'm always open to a better solution if anyone finds one.

barbult

Some hair products come with morphs to move the hair away from the forehead a little bit. That is helpful in resolving those black marks.

crosswind

Changing instancing or tweaking morphs on the hair really work for many people. Just have some more experiment ~~

Highland

crosswind said:

as well as the eyes with black sclera... Because your character is far from the World Center ( XYZ 0,0,0 ), instances of geometry of hair cap / cornea and sclera caused the problem. You may check the values of XZ axis of her...

Solution: Go to Render Settings pane, change "Instancing Optimization" to Memory or Speed.

I just had black sclera.. I changed Instancing Optimization to Memory and that fixed it. Thanks Crosswind!

crosswind

Highland said:

crosswind said:

as well as the eyes with black sclera... Because your character is far from the World Center ( XYZ 0,0,0 ), instances of geometry of hair cap / cornea and sclera caused the problem. You may check the values of XZ axis of her...

Solution: Go to Render Settings pane, change "Instancing Optimization" to Memory or Speed.

I just had black sclera.. I changed Instancing Optimization to Memory and that fixed it. Thanks Crosswind!

You're welcome ~ and happy rendering！