SSS Across Subtools
Calculates SSS Across Subtools. The SSS Across Subtools button will take all subtools into consideration when calculating subsurface scattering. If this button is off, SSS is calculated as if each subtool is lit individually.
Subsurface scattering Rays Count. The Rays slider will set the number of rays used in the subsurface scattering calculation: A higher number will give softer SSS, depending on the Angle setting. Increasing ray number will increase render time.
Subsurface scattering Maximum Angle. The Angle slider should normally be left at 360 but reducing the value will narrow the Subsurface Scattering effect in relation to light direction.
The Res slider will set the SSS resolution in pixels: This figure is effectively the image size (independent of document size) that ZBrush uses internally to calculate the subsurface scattering. Lower settings will render more quickly, higher settings will give greater accuracy. Sometimes a lower value can give the desired result with less processing overhead – for example, when a weak SSS effect is required.
The Blur slider will set SSS blur radius in pixels: Higher values give softer, more blurred subsurface scattering. This is related to the Res slider and should be adjusted in tandem for the same effect. For example, if the Res slider value is changed from 500 to 1000, a Blur value of 4 should also be doubled to 8.
The VDepth slider will set view depth offset in pixels: The SSS calculation is offset towards (with negative values) or away from (with positive values) the viewer.
The LDepth slider will lights depth offset in pixels: The SSS calculation is offset towards (with negative values) or away from (with positive values) the light sources. Settings towards the light source tend to create greater SSS, settings away from the light result in less SSS.
Activates Sub-Pixel-Depth Calculations. Gives greater SSS accuracy. Normally left on but turning off will speed up render times when experimenting.
Reference Guide > Render > BPR Sss