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TaKIKO
07-27-2010, 08:42 PM
Hi,

I was looking to see if anyone had or knew of any online refernce that goes over the workflows with using this shader. I've been playing with the shader a bit an I am not exactly getting the results I want. The only info I could find is this : http://www.spot3d.com/vray/help/maya/150R1/vrayfastsss2_params.htm Ive read over but I was looking for more workflow techniques.

Thanks,

Michael

Hasnz
07-31-2010, 01:48 AM
Being used to the great Mr fast skin shader ( which is specially designed for this purpose ) , most artist might have problem , but seeing that Modo as only a single SSS channel and I have seen great skin renders in that renderer as well . I had almost quite this shader initially playing but getting a little hang of it now . Its quite capable and there are some great Render examples around .

Flickering not tested yet . I found it dead slow initially with GI compared to MR

Comparing to MR sss shader the 1st option that came in my mind was the separate control over the back scatter . This is something that we will need to control by textures on the scatter radius and phase function .

Epidermal option is missing and is a requested feature in the future updates . But we can come close to something by balancing the SSS and diffuse values .

Prepass blur - Ill keep this value to 0 , was giving very dark results with positive values applied by the presets ( with GI on ).

Overall and diffuse color pretty much functions the same .

My Mr to sss2 maps would be like
Epidermal > Sub surface color
Subdermal > Scatter color
Back scatter controlled by Scatter Radius ( textured mapped ) .

The results are 70% comparable with my current test . I cant share any images as it was done on a production model , . But maybe we can try and compare a little more with the Globolus model that MasterZap provided with his sss tutorial :) .

Hasnz
07-31-2010, 11:10 PM
some tests with globolus model . The results can be pretty good , once we know the nature of the sahder . More control over individual radius will make it for easier to control . One concern is that itis Slow atm .


http://img267.imageshack.us/img267/4798/globolussss.jpg (http://img267.imageshack.us/i/globolussss.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

TaKIKO
08-03-2010, 03:13 PM
Thanks for the detailed replies. I agree the sub surface does not have as much control as some of mental rays ss shaders. Would you know how to comp the sub surface pass using all the raw passes and filters.

Hasnz
08-05-2010, 12:28 PM
Normally , It should be added similar to Specular and Reflection Pass . More info here :
http://www.vray.info/tutorials/basiccomping/ .

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