Help with hair shader

[Rikk The Gaijin]

I'm really struggling to find some good settings to render hair in a realistic way.
I want them to have all the physical properties real hair have, the shininess, the nice rim light they can pick up, and the scattering when are lit from the back.

The best I came up with is using the specular material, with 0.2/0.3 roughness, 0.1/0.2 scattering, some RGB value in the absorption, and playing around with scale and scatter direction, but they always look wrong, they kinda look like made of fiberglass or something...
Does anyone have any tip for realistic hair? I wish Octane had some dedicated hair shader, like Lagoa or Vray...

Here some example of what I'm trying to achieve:

[xxdanbrowne]

Are you using transmapped or high poly hair (like zbrush fibermesh)?

[Rikk The Gaijin]

Are you using transmapped or high poly hair (like zbrush fibermesh)?

High-poly hair, it's impossible to get realism with flat planes.

[xxdanbrowne]

Chopper and face_off were playing with fibermesh hair over in the poser section of this forum a few months ago. I don't know how far they got.

[face_off]

High-poly hair, it's impossible to get realism with flat planes.

ZBrushcentral had some good shots from "The Last Of Us" which used planes and looked convincing. Not sure if it would be up to the standard you need though. I liked the polyhair approach because a) it could be animated, b) the falloff node could be used on it, and c) it is possible to get a lot of texturemap reuse on each of the planes. But no SSS might be a problem.

I spent some time exporting polyhair from ZB into Poser and rendering in Octane. The trick seemed to be to have many hair groups, so that you can use different Octane shaders on each (since there are no UV maps on ZB polyhair to use texturemaps). I got far enough into the process to know that it was a bigger undertaking than I had time for.

I'll be eagerly waiting to see what you come up with.

Paul

[Rikk The Gaijin]

High-poly hair, it's impossible to get realism with flat planes.

ZBrushcentral had some good shots from "The Last Of Us" which used planes and looked convincing. Not sure if it would be up to the standard you need though. I liked the polyhair approach because a) it could be animated, b) the falloff node could be used on it, and c) it is possible to get a lot of texturemap reuse on each of the planes. But no SSS might be a problem.

I spent some time exporting polyhair from ZB into Poser and rendering in Octane. The trick seemed to be to have many hair groups, so that you can use different Octane shaders on each (since there are no UV maps on ZB polyhair to use texturemaps). I got far enough into the process to know that it was a bigger undertaking than I had time for.

I'll be eagerly waiting to see what you come up with.

Paul

I would love to post my tests here, but I'm under a very strict NDA, so I can't...
Perhaps I can make one version just to be posted here, unrelated with my current task...
Also, I never used the falloff node, I need to search the forum how to use it (if anyone can link me some page I will appreciate it), I need to try it out.

[xxdanbrowne]

I still don't clearly understand how the falloff node works but Fooze talked me through how to use it to make a fabric shader in this thread:

http://render.otoy.com/forum/viewtopic.php?t=34069

[Rikk The Gaijin]

Thank you, I'll try that out!

[Davve]

maybe you can learn something from this

http://help.chaosgroup.com/vray/help/20 ... params.htm


I'm planning to do some hair shader tests in the near future, really curious what you come up with this far.

The most significant part of hair shading seems to be the dual specular component combined with proper transmission.

David

[Rikk The Gaijin]

I tried VRay hair shaders, not only it's ridiculously slow to render, but it doesn't look very good in my opinion. I've found some interesting settings in Octane, but still far from being realistic. I can get one characteristic at the time, for example, I can get the nice back-scattering OR the specularity, but I can't get them both, or at least not the amount I want...