Before setting up the shaders I did a displacement check (Fig.11). In this part I will focus on the skin shader.
VRay Fast sss 2 is a fantastic shader that allows you to obtain the best results without creating too many maps. Now we walk into a section where there are not definitive settings even if you are modeling in real-world scale. Now I analyze the most important parameters for the Skin (pink) preset (Fig.12)
Values below 0 cause many artifacts so it's better to use a 0 value, which is what I did during the test rendering. I switched to 1 for the final render, keeping in mind that the render time doubles.
Scale and Scatter radius are linked together and personally I prefer to use Scale and leave Scatter radius with the default value. This is one of the most important settings because it defines the model's scatter amount. Higher values are equal to high scatter and the shader starts to look like wax. There is no set parameter you should use; it all depends on your own taste.
Note that this value actually blends between the diffuse and sub surface layers. I left this value at 0, but eventually you can add a map to the amount to lessen the scatter effect in certain spots of the face.
Sub Surface Color:
This is the parameter that affects the real look of the skin. I assigned the texture I created in Mari to this.
Compared to the skin pink preset, I desaturated a bit the color (in this case too, it's a personal choice).
This is a very important setting because it determines the scatter depth. High values produce a superficial scatter and low or negative values produce a deeper scatter. Most water-based materials exhibit strong forward scattering; that's why I used values between 0.7 and 0.9.
I left this as a solid white color, even though many other artists use a light blue. If you need a specific specular effect you can control it through a black and white map.
I left the default value because it's physically correct, but if you want to obtain different specular effects you can lower it.
It's a fundamental parameter since it determines the amount of glossiness of the skin. At first I determined a basic overall value (from my experience between 0.350/ 0.45). The face skin doesn't have a solid glossiness all over since there are oily spots, therefore I used a map to control its intensity. To have the maximum control I used a layered texture with a basic grey (value of 0.4) and a map I layered over it in Lighten to control the highlights (nose, lips, chin, eyelids, forehead and ears).
It is a value to check in order to have physically accurate reflections
Another important parameter if you want to get realistic skin, although once it's checked the render times will increase.
For a still render like mine I set the value to 0.1. This setting can be used in animation to avoid the flickering of scattered objects.
And this is the final look of the shader (Fig.13).