Very interesting. To my eye, Ambient Spot is very similar to SSS Spot. But Infinite is different. I found that you can't have depth mapped shadows with Infinite lights - so the SSS Infinite won't be shadowing correctly for the FastScatter node. So the question still remains, is the FastScatter node giving any results in these renders that wouldn't come from just using ambient.

Creator of PoserPhysics
Creator of OctaneRender for Poser
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