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animate1978 / MB-Lab

MB-Lab is a character creation tool for Blender 4.0 and above, based off ManuelBastioniLAB
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SubSurface Scattering (SSS) Research #284

Open animate1978 opened 4 years ago

animate1978 commented 4 years ago

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

Screenshot from 2020-07-12 09-19-36

Here is the table of reference.

SSS radius table Blender-02

Here I have created a render using the current values

SSS_default_mblab_values

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

SSS_new_mblab_values

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

animate1978 commented 4 years ago

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

SSS_default_mblab_values_HDRI

And the changed values using the same HDRI.

SSS_new_mblab_values_HDRI

Again, not much of a difference BUT...

animate1978 commented 4 years ago

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

EEVEE screenshot

TOON_GIRL_new_SSS_EEVEE

Cycles Screenshot

TOON_GIRL_new_SSS_Cycles

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

ldo commented 4 years ago

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

Here 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 commented 3 years ago

random_walk_SSS_010 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.