Human Skin WIPs and Tips (Everyone feel free to post your own skin WIPS here too)

#981

:slight_smile: Heres my attempt with skin shading and texturing.

#982

Here’s a Closer View.

migiSkinClose.jpg800x600

#983

Leigh, are you using XSI too?

#984

Many apologies if this has been asked bofore, I couldnt find it.

There is a ton of info on the shders for skin diffuse, but Im troubled in getting the proper highlights, Ive tried for quite a while now and all my shaders end up having circular plasticy highlights, could anyone please explain to me how to setup the highlight shader (max scanline or MR)

Currently I have a gradient ramp for the spec color with green leading into deep blue w/ normals and for spec level I have another gradient ramp which has the same thing but is much more intense at the edges. It doesnt seem to work at all.

#985

pretty much anything you’ll do with either Phong or Blinn will end up looking plasticy : human skin by default (not wet / sweaty…) is mildly anisotropic (negligible) but has a fairly strong forward scattering quality which shifts the highlight off of the reflected axis. as an example : hold up your hand towards a light source and notice how reflective your skin is at grazing angles.

as long as you cannot rotate the specular lobe down, your highlights have to be faked (see Stahlberg’s works) and those fakes fall apart with animation. a physically correct alternative exists but isn’t available to any commercial software that i know of.

#986

The keyword is the reflective.

Specular IS a fake substitution of the reflection of light sources. Human skin is VERY reflective (depending on its oilyness, sweat, environment, etc.) So using reflection (with HDRI images) helps a lot. Take a look at the same face in different environment. Youll notice the reflection of the environment. Its blurry, just patches of colors, but there it is.

Id make a shader that reflects more at glancing angles, while increasing its blurryness. Why it`s good? Because on glancing angles there would be an intense, but spreaded reflection. there are several other factors, but replacing the specular with refelction will add realism, and color-variations also.

#987

100% correct j3st3r - though IBL is not always a very practical way of lighting things and most rendering softwares / shaders tend to have problems with large filter size lookups into environment maps that create nasty artefacts.

#988

My experience is that IBL works just fine even in print resolution. The key is that you should use IBL as the fill component of the light rig.

#989

as long as you cannot rotate the specular lobe down, your highlights have to be faked (see Stahlberg’s works) and those fakes fall apart with animation.
afaik my ‘fake’ works with animation, the lobe may not be shaped exactly like it should but imo in the ballpark. :slight_smile:
It’s not so much a fake in this case (as my translucency fake is), it’s more a matter of manually constructing that dang lobe, from 2 layers of shaders instead of 1.

edit:
Oh yes, from the point of view that all CG specularity is fake (since specularity is just another type of reflection) yes then it could be said to be a fake. It would be better if spec could always be done with image-based lighting (though that’s a bit slow and tricky in some cases), but even so using a layered fresnel based shader is a good idea.

#990

Although proc intensive, using the reflection shader is giving me much better results… of course now I have the trouble of figuring out how reflective skin is. Currently I am using fresnel and IOR of about 1.45, is this right at all?

took half an hour… bleh…Metal(lume) shader is the only one I can find with blurry reflections, I suppose I should just blur the HDRI instead.

#991

This is my latest attempt:

I think that it is wrong to “simulate” the behavior of the skin. I suppose imitate is a best working mode. And fastest.

If you try to find your skin between the mathematical parameters, you`ll get incorrect results. Few important factors in succesful skin

  • model - without good model, the light won`t behave as you expect. The shading will reveal all the mistakes, and it will fail
  • light rig - without good light rig you cannot simulate the environment of the human skin. We see human skin all the days. I spent few dozens of shots i=of human faces in different environments, face on the street, face in the mall, face under cover of a balcony, etc. And the same face never looked the same. Simulate the environment, with different lights (HDRI`s do the best as fill light)
  • reflections - everything is reflective (at least 3-5 percent), human skin also. Observing the reflection on the skin helps a lot to create convincing skin.
  • Specular - my opinion is to avoid specular. Specular is not as good as reflection. Specular IS fake reflection of the light source. It`s more convincing that if you like to have your light reflecting on a surface, give them geometry by attaching luminous planes to light, etc.

But that`s just my personal opinion.

#992

not a face of course, but a piece of an arm from a WIP i’m working on

only bitmap is the colormap, bump and anything else procedural.

done in cinema 4d 8.5 with translucent free and layering/fusion in all channels.

ehat do you think?

#993

This is the latest iteration of my the shader I’ve been tweaking using Zap’s mi_SSS shader. Any feedback would be helpful in furthering it’s development:

#994

Hello!!! my english is very poor so only i will say this thread is great! Here is a picture of my best attemp for skin texture of a face.
And in this page (this is a bonus jaja, is a picture of mazzinger 3d modelled one mouth ago).
Coments please! good luck.

http://gameno.8k.com/photo.html

#995

Tocpe: I really like the feel of your skinshader, the mi_sss_shaders are really cool, and you’ve done a great job so far. Great reflections and softness. I think adding more moisture to the eye
area would give the model more life. Also I think a subtle peach-fuzz layer would improve your skin. And I really think you should re-model the ears, unless you are going to cover them with hair :slight_smile: Anyway, great job so far! I’m keeping my eyes on this one.

#996

Thanks Jan,

I plan to work on implimening a peach fuzz layer---somehow---just haven't figured it out yet. :) I'm working on tweaking the eyes now trying to add "life" to them along with the wetness you mentioned.

As for the ears, yeah, they’re pretty mangled, but I’m not too concerned with them at this point. For one thing, this is a test model, and eventually the ears will be covered by hair on the finished model anyways. :slight_smile:

Thanks for the feedback. And please keep ‘em comin’ guy and gals I really want to push this shader to the limits. :slight_smile:

#997

This is my attempt

#998

Hey, that`s really cool

My only crit is about the nostril. The nostril is not a hole, but a complex form. Anyway, it`s a really good looking skin

#999

Thanks J3st3r

I know the nostrils crap. that’s laziness for you

there’s also no model to the right of the render :slight_smile: and the hair’s a cheat too. it’s photoshopped on.

The skin texure on yours is good… I think you’re right about using reflection rather than spec, I used a combination on here.

its funny how many people seem to go over the top with SSS as if SSS=realism… I would say the effect of SSS is very subtle on skin and is hardly the most important part.

#1000

I like what you’ve come up with - did you use an MR SSS shader?

One small crit - your forehead looks a little ‘dry’ maybe? Although, this could be a crit chalked up to POV…some people do have dry foreheads :slight_smile:
Do you know if your high spec areas are a little over-blown because of your lighting or spec settings? I like the overall ambient feel to it though, the tones are very subtle and realistic.

Good job!

DD