AOA Subsurface Shader, conversion from normal skin

sriesch

Can somebody point me in the right direction for instructions on converting a normal figure's skin to use the AOA Subsurface Shader (3DL) to a vaguely realistic skin texture?  Either it seems to have no significant effect, or it's impossibly far off from anything that makes sense.  I can apply a random preset like Gummy Aqua.duf and that works fine, so it doesn't appear to be related to my lighting and the shader itself works, just not when I try to combine it with a normal skin material.   I'm sure it's just a matter of adjusting/setting the appropriate parameters, even a good starting point would be nice. Thanks!

DaWaterRat

I usually cheat.

That is, both Silver and Fred Winkler Art use the AoA subsurface shader as their current default for 3DL characters, so I'll pick one of those and Right Click to apply the shader (telling Daz to ignore maps).  Sometimes I'll have to fix the UV map, but that's not too difficult.  I start adjusting from there.

That said, you'll want to set the subsurface to a given strength (I prefer it low, others prefer it high) and bring the diffuse down (how far depends on what you're looking for), as well as setting up the velvet for the apropriate material zones (not fingernails or lips, for example)

You'll also need to adjust the shading rate and be sure that the Character ID is on something other than 1.

mjc1016

DaWaterRat said:

 

You'll also need to adjust the shading rate and be sure that the Character ID is on something other than 1.

And not the same as another character using the same shader...

sriesch

What/where is character ID?  I don't see that as a parameter in the Surfaces pane.

DaWaterRat

sriesch said:

What/where is character ID?  I don't see that as a parameter in the Surfaces pane.

Sorry.  That should be Group ID.  I misrememberd the exact parameter name and I didn't have DS open at the time.

 

sriesch

I see the group ID parameter, thanks.  What is it's purpose, why am I avoiding 1 and keeping them unique for different figures?

Hmmm, I'm having no luck.  Still trying random combinations to see the effects.  Although I did stumble across a setting that gives the illusion of much stronger rim lighting, which is potentially useful if completely unrelated.

I'm trying to apply it to V3, so I don't have any existing SSS product to use as a starting point.

On a related note, although this is for Genesis and not V3, for future reference is it possible to apply the Subsurface Toon Shaders ( http://www.daz3d.com/subsurface-toon-shaders ) to a Genesis figure that already has textures as was described above, and combine the SSS effect with the diffuse textures, or will that product simply replace them?

DaWaterRat

It should work correctly with the CTRL/Ignore proccess and not replace things.

I didn't write the program, but I think it's similar to Group ID in pwEffect, which determines which effects are "in front" of other effects or something like that.  I know that if you have two things with the same group ID but different settings, the settings interfere with eachother in weird ways.

Now, a quick caveat, I don't actually try for super-realistic skin in my own artwork, so what works for me will probably not quite work for you, but it's still a place to start.

I leave Ambient alone, have diffuse at 100% and Subsurface strength at 25%.  Velvet I sometimes use, sometimes don't.  You'll also want to be sure that Subsurface off-On is set to 1 (on) and put any subsurface maps in the subsurface color, or you can adjust subsurface color to whatever you like.

Then there's the absorbtion, which I think determines how much of a given light spectrum is absorbed by the figure, so a high blue absorbtion results in less blue, etc.  There are presets here, feel free to play (I have one render somewhere that I made a genesis figure a really nice haunting icy blue without having to go hunting for the right skin maps.

Be sure that Displacement is set to 0 unless you have displacement maps.

It is also possible that the effect you want is best done with some other shader, such as UberSurface (which is also included with DS, and which I can't help you with, because I use it only when I absolutely must.)

Also a lot of the effects will only apear "correctly" when you render in 3delight.  The openGL viewport won't show what it really will look like.

sriesch

Here's what I'm getting with the above setting test (left).  Adjusting the velvet does things similar to the right screenshots.  (Sharp shadows is an unrelated problem I also need to resolve later, but I'm not worrying about that for this test.)

Richard Haseltine

GroupID labels surfaces as going together for the SSS effect - if two surfaces on sepaarte objects have the same GroupID light can bleed between them (and if two surfaces on the ame object have different GroupIDs light won't bleed between them, hence giving the teeth or eyes diffrent values). Also, in the AoA SSS sahder at least, each group of surfaces may have only one value for several of the SSS-related properties, if they don't then weird artefacts are produced on rendering; two characters with the saem GroupID will almost certainly differ in at least some of those settings and so will render poorly.

sriesch

Thanks for the GroupID label background info!