I realised my render comparisons don't really illustrate much beyond the use of the HSV node.

Richardson & Snarlygribbly have both hit (in their own ways) on what I think I was trying to get at here.

We tend to think that a photo reference of skin used as a diffuse map will give a (more) accurate render, but as Richardson points out any photo of skin already contains colour & tonal information that we will eventually be trying to simulate using 3d shaders & lights, based on the conditions under which that photo might have been taken.

Using a histogram to examine the colour information of a skin swatch is useful, but surely it will give us results that are only useful to compare with a final 3d render of skin under a similar set of lighting conditions, not the composition of the diffuse component used to achieve that render (that's how I see it at this point in any case).

Now, I'm thinking that bb's shader setups (that most of us are using variants of) partially account for this by not using the Scatter nodes built-in material option and give us very passable skin, but there's still a lot that's being calculated on the basis of colour information that probably shouldn't be in a diffuse map.

It's a simulation of course, but I wonder how much is being skewd by the maps we're using at present, and the shader balancing act employed to deal with that kind of diffuse component.

 

PoserPro2014(Sr4), Win7 x64, display units set to inches.

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