I have picked Jim Talbots Hipchick character as manequin for this tutorial. She already sports very good texturing, but lacks of specularity and bump maps for the face (except lips). Good spec and bump maps will greatly increase the realism. for the purpose of the tutorial i have deleted Hipchicks hair.
I'm using a very simple setup for the chor, the only non-standard bit about it is that it shows the dark side of the model. The Light is a sunlight with the default settings, parallel to the xz plane.
The settings for the material are taken from Jim Talbots model, the camera settings are standard.
you should take care that the specular settings are very low, maybe even set to 0 for now.
Rendering the start setup shows the nice work Jim Talbot did with texturing Hipchick. but it also shows what standard shading is doing wrong with skin: the head has a clear light and shadow zone.
2 Activating the Toon Renderer
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 Activating the toon renderer mainly shows two problems: 1. A:M does not shade beyond surfaces that cannot "see" the light. 2. The toon lines are not really what we call realistic skin shading |
3 Deactivating Shadows
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 The first issue can easily be outmaneuvered with turning shadows off for the camera. The downside of this is: the surface cannot receive shadows anymore. Turning off shadows only works for toon rendering. |
4 Deactivating Toon Lines
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 The second issue is even less challenging, the toon lines can be turned off in the camera settings. You'll have to select override lines and then set render lines to off. But what we got now is looking rather flat. |
5 Change the Material to Toon Falloff
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 Now we are starting to tweak the material. For the toon shading method select toon with falloff. To create the gradient as you see it here click the right end of the gradient bar, leave the key there, then click the left end and pull the key to the center. The shading you are getting now is exactly the same as the original shading was. Except now we dont have any more shadows because we turned that option off. |
6 Overshooting
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 Pulling the left key back to the left end of the gradient you will see that now we are able to light even areas. With this effect we can simulate sub surface light transport as it happens in marble, wax and skin. The left of the gradient represents surfaces that are directly looking away from the light, the center is shading surfaces that are parallel to the light ray (aka terminator, shadow perimeter) and the right is shading surfaces directly facing the light. |
7 Tweaking the Gradient
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 You should take some time to fine tune the gradient. I have settled here for a quite sharp shading with a line of light beyond the shadow perimeter. I know it looks a bit over-exaggerated (maybe even a bit metallic), thats why i made that line of light just a bit darker for the following images. |
8 Adding Specular
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 Once you are satisfied with the shading you can add the specular. I chose to make it maximum size and quite low intensity. I changed the Specular color to a very light blue. |
9 More Tweaking
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 I have changed the surface color a bit and increased the specular intensity to give the render a more realistic look. You can feel the absence of specularity maps as the specular highlights are looking very smooth as on plastic, but thats a task already covered in other tutorials. I am not very happy with my shading choice now, but i can go back to tweak the gradient any time. |
I hope this tutorial was of some use to you, please let me know what you think my mail mbricman@kci-group.com.