SubSurface Scattering (SSS) Research

[animate1978]

Looking around the Blender Devtalk site I came upon a post related to SSS - https://devtalk.blender.org/t/better-explained-sss-with-presets/14351

The reason for this issue is that the SSS radius of MB-Lab Skin may be incorrect at this moment.

Currently the SSS radius values are being controlled by the Scale Vector Math node

Here is the table of reference.

Here I have created a render using the current values

Here is the modified version using the above table as a reference using the "Skin 2" values

There is not much difference but you can tell, possibly going to change this for release.

[animate1978]

Here in a more "natural" lighting using an HDRI, the "default" SSS radius setting in MB-Lab

And the changed values using the same HDRI.

Again, not much of a difference BUT...

[animate1978]

What is interesting to note is that on Toon Girl, I plugged in these values and got this...

EEVEE screenshot

Cycles Screenshot

So on the Toon Girl model the above SSS chart is coming in REAL handy!

[ldo]

For those having trouble, as I am, seeing the difference between those two “natural lighting” examples above, try downloading them and viewing the difference, for example with G’MIC:

gmic 87250550-3c264400-c42b-11ea-824e-7ce649815598.png 87250816-24e85600-c42d-11ea-9700-98f557cbb345.png sub equalize normalize 0,255 output diff.png

is the diff.png I produced. I think you can ignore the coloured noise over most of the face, but note the highlights around the eyes and lips.

[animate1978]

For those interested I have changed the SSS method from Christensen-Burley to Random Walk. This gets rid of the glowing red effect seen around the eyes.