first attempt at realistic skin - C&C welcome

[Rens]

It could use a spec map to break up the specular highlights.

The face looks somewhat untextured and wax-like.

Overall pretty good but it seems a bit unfinished.

Here are some tips which you may or may not have used in your render already, hard to tell from this image. I'll just throw them out in case you or someone else might find this useful. :)

Imagine a piece of skin with one half lit up by a bright light/sun and the other half in the shadow of some object in front of it, creating a sharp division.
Scattered light in the skin is more yellow or natural very close to the shadow edge and gets more red further into the shadow area.
It's hard to tell from the node tree you've posted, but you could use a yellow-orange colour with small scatter radius and then a red-orange layer with larger scatter radius. Use red for back scatter. Then you could desaturate the diff map as most of the red colour will come form the lower layers (as in real skin). Probably add some brown to all maps depening on how much pigment is in the skin.

The blue or slightly darker edge you might see in real skin close to the shadow edge (but still in the lit area) is caused by a lack of scattered light from the shadow side. It actually isn't blue, it's just less red, making it look blue. That's the same reason some veins look blue. They absorb the light travelling through the skin so in that place less red comes back up.
Red veins probably are thinner and closer to the surface. And, as far as I know, there is also a difference in how much light blood absorbs depening on the amount of oxygen in it. But that's likely not something to really worry about.
You can actually see the bigger veins with a laser pen in a dark room. Laser pens are also a good way to see how much the light scatters under the skin, giving you a real unit value to base you scatter radius on. Really, laser pens are awesome if you want to know about how materials reflect and scatter light.

I've attached a quick example. The red-orange subdermal map user a larger scatter radius and has a B&W vein texture multiplied on top. You can see that the skin looks more blue in the places where the subdermal map is darkder. In real skin you wouldn't see those veins as clearly defined in the dark area, but this is the mr fast SSS shader, which sort of uses textures as stencil after blurring the light map, it doesn't really bounce the light around. So you could blur the vein texture beforehand and also make them light-dependent (falloff map?), so they won't show up as much in the shadow area.

Anyway, that's some stuff I noticed while working on some skin shaders recently.

That NodeJoe thing looks pretty cool. Can it be used with all renderers and shaders? Their site is down so I can't check.

[RobertMayer]

Thank you, for the tips - they actually make a lot of sense.
Currently rendering out a new version which I will post when it is done.

I focused on improving specularity in these, including adding a spec map, and a double-layer spec system using a blinn and a velvet shader.
I am very pleased with the results.

Back onto SSS, I just started using the fR-FastSkin shader today, and From what I can tell there isn't a great deal of information out there on it. More experimentation is required.

Here are the latest versions
http://img521.imageshack.us/img521/5746/skintest5gw2.jpg
http://img520.imageshack.us/img520/9638/skintest4eo0.jpg
http://img520.imageshack.us/img520/2002/skintest3fe0.jpg


in regards to NodeJoe, it is absolutely wonderful. Realistically, I can pretty much declare I do not see myself going back to Max's material editor, except as a bin. It is especially useful because I have a three-monitor setup, and I keep NodeJoe maximized on one of my screens.
It is compatible with any material, map, and Renderer that Max is compatible with (except script maps, from what I can tell. I once had a Color map that was made through a script that would force MAX to crash when you open nodejoe, but I since got the Blur Solid-Color and it works fine).
Rumour has it, the developers will be adding math functions, as well, in the next release, as well as customizable categories for their material pool. I think I read that they are also making it so you can have "Pages", so you can access multiple spreads of nodejoe with a dropdown menu - very useful
Too bad the site is down, for I would reccomend it to anyone.

[Rens]

Thanks for the info. Looks like NodeJoe is one cool little plugin. I'll check it out once the site is back up.

The new renders are looking good, though it could use some more variation in colour. More red in the lips and cheeks, maybe a bit more 'blue' under the eyes, that sort of thing. Some wrinkles as well. Plus the SSS scattering seems a bit too spread out in the first image.

[RobertMayer]

I think I may have it, or at least, something a lot closer than anything I've had before.

http://img48.imageshack.us/img48/7227/skintest6ih3.jpg

Now, the problem is, I don't know if its too red or not.

[Rens]

Yep the guy looks much more alive now. Maybe a bit too red, yes, especially in the shoulder area.

[RobertMayer]

http://img244.imageshack.us/img244/4372/skinshader7oo1.jpg
Added a lit/shadow falloff to the "dermal" layer, with an amber-orange in the lit, and red in the shadow.

Any other sugguestions?

[toontje]

If you having this much problem to achieve realistic skin, why not import your model in Blender and render it? It has SSS with 2 default skin settings. I've seen some 99.99% procent realistic skin rendering already done with this SSS shader.

[RobertMayer]

A couple of reasons. For one, I don't have blenderm, lol. The other reason is because I had a hunch on how to do SSS with FinalRender without using their (REALLY) slow skin shader. Thus, this: an excersize, if you will.

[peachstapler]

Looks a lot better. I'd like to see your work on the ears with a back light.

[CGTalk Moderation]

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.