Texturing with the misss_fast_skin shader Infosheet
by Richard E. Fallat
This is just an example how one can go about texturing with the misss_fast_skin shader for mental ray. I am by no means an expert when using this shader, but I found some interesting things while working with it.
One of the most crucial parts of working with this shader is to keep your layers in your .psd file and then just save out .jpg's or .tga's for your maps. Yeah, your psd file will end up being HUGE...mine was upwards of 500 megs (a bit much but I'm anal). It will pay off in the end because if you have layers like for 'veins' or 'fatty blush patches' they can directly correspond to the different sss attributes. Like for example the veins that show up in the ear...you are probably not going to want those to stick out very much unless it is backlit so I basically had them at 100% opacity for the back scatter and then lowered the opacity considerably to like 10% for subsequent maps. It's also probably a good idea to put notes on your layers. For example: ear veins 80%diff_10%overallcolor_100%backscatter |
Here's an example of the different maps used. Some of them are older versions then used for the final, but you can still get a good idea on how they were used.
A good place to start is with the diffuse map. I basically overexaggerated everything in this map. everything is at 100% opacity and saturation. You can control how much of this map you want to 'mix' with the sss layers by tweaking the 'diffuse weight'. Mine is set at 0.4.
The next map I worked on is the overall color. This is basically an overall multiplier. So things like eyebrows won't have scattering effects on them. I also desaturated this map considerably due to the fact that it is a multiplier.
Here's the back scatter map. The black painted on the nose is there to block the back scattering effect. You can get the same results by making a 'back_scatter weight' map.
Subdermal Map
Epidermal Map
Bump Map
Primary Specular Map. This map basically controls the specular highlight that has a more diffusive falloff. I definately give credit to "d'artiste Character Modeling" book and Francisco A. Cortina for these next couple of maps.
Secondary Specular and Reflection Edge Weight. This is just the Primary Specular map with noise added to it. It'll give a nice broken specular and rim reflection.
Reflection Weight. This is a very crucial map. It can really enhance the reality and beleivability of the skin. At the parts of the skin that look wet like the lips and the tearduct your probably gonna want some reflectivity. You can also get a glitter effect by adding high frequency noise where the makeup is in the reflectivity map. Create an HDR sphere and you can definately notice the results of the reflectivity.
Again, I am by no means an expert at texturing with the misss_fast_skin, but hopefully this can get you on the right track and serve as a starting point. I would also like to give thanks to the "d'artiste Character Modeling Book." It has some great stuff in there on texturing, shading, and even hair!