A 3DC project_ a SSS study

I was asked to send some 3DC only projects (for a show I think) , this is exactly so, its a BI render though, I think I figured out a way to render some marble tex using SSS. DOF sharpening and tonal balance via nodes as usual, vignette and resizing via ps. Its a low poly model, + normal_map. What do you think?

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Very nice Michalis!
Illumination and materials are very good!

thanks tungee, now I’m testing indirect light with SSS. Normally is not the best but I have some interesting results here.

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Very nice.

One suggestion: I would move the camera back a bit and make the image size a square.

monsterkodi, thanks, I may do this. For the moment and for the first time using Indirectlight, I see some serious sculpting problems here lol. I think, soon enough, using IL, we’ll be able to kick some mental ray a**es. This IL gives back all the lost details from blurred SSS.

That is interesting! I really hate how sss can really flatten stuff out!

I really hate how sss can really flatten stuff out!

Exactly Michael W. Lets try it to a high poly model now. I read somewhere in this forum that indirect light and SSS are not good friends. Lets see if this is true.

Another test using SSS + blender GI. A more convincing marble texture. Baked AO is a problem with sss+indirect lighting I’m afraid. I’m using a color a normal and a spec map here, simple sss (no nodes).

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There seems to be problem above ear. I guess it’s GI bug because it looks like bounce light is to strong for this shadowed area. Why don’t you try use raytrace GI? It work very well imo

Thanks JoseConseco. What is raytrace GI? Where is it? Please help, I really don’t understand. If you mean the other tab than approximate then this simply doesn’t work. If you have another experimental build in mind then I have a lot of them and they simply don’t work either. In a matter of fact v2.49b is the only blender build that works for me and has an excellent GUI. I cant even sculpt in v2.5 so far. Sorry for this, I lost my temper.

Just grab render branch from graphicall:

And in gather option select raytrace + cache; samples around 32 should be ok. This way you will have raytraced indirec lightning and GI. Works with sss too. Hope it helps.

About raytraced GI - it mean it is calculating photons their path and energy. Enabling cache option will speed this up.
Aproximate GI is, as far as I know, just trick based on coloring ambient occlusion. I’m not sure though.

Thanks, I’ll wait for an official build, enough with graphicall. I’m on a mac actually and most of new builds don’t even work for me. I have to wait. 2.49b rocks, 2.5 I don’t know maybe next year.

Aproximate GI is, as far as I know, just trick based on coloring ambient occlusion. I’m not sure though.

Its GI but not good enough. And its slow on my 16 threads 2xeon because the AO is one thread calculation. This makes me say again… in one or two years maybe maybe…

It looks as if your experimentation has been very successful, top notch work! Well done.

Thanks seanser, its too kind. An interesting material here thats all. Long way to a real aged marble texture.

Here’s an aged marble with all these oxides. Maybe I’m starting to understand blender SSS who knows.

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I don’t know i you have seen this but I really like this example of marble:
http://www.blender.org/development/release-logs/blender-244/subsurface-scattering/
made be Enrico Cerica. Maybe he can help you

JoseConseco thanks. Well, I’ve seen these of course but this is a statuette. A visit at Athens Museum will give you a completely different impression about real ancient marbles. These are more like flesh but this is just an impression. In any case I cant see any serious refraction there. So I lowered the value of refr at ~0.4. In any case these look very crisp and detailed. Very! Here is my problem using blender SSS. Mental ray can be crisp, blender should. There is people here who believes that mentalray is not as good as blender (SSS). I shaw this too.
Take a closer look of this photo taken at AthensArcheologicalMuseum. Crispness and a good GI should do most of the trick but some SSS is needed. No waxy or blurred effect though. Is this possible in blender? BTW latest GI builds didn’t work for me. I stay with the official 2.5.2, 64bit Mac.

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Well then, only way I can think of getting softer shadow, without loosing crispness is by combining 2 materials - one with sss mixed with diffuse only material. Basically I would duplicate your material, then make single user and disable sss. Then you would combine them in node editor.
You may want also to map where would be more sss, and where more diffuse by texture (just like here http://www.blender.org/uploads/pics/mat_nodes_mix.png).
I would also lower spec value and hardness. I’m just guessing so I’m not sure if it will work, but I think it’s worth a try

Oh thank you JoseConseco. This is very interesting, The use of an sss map!
I already did some experiments combining two materials, in some cases its similar to combining two renders via pp (OK not exactly). The difficulty in SSS is this IMO:
In real world a sculptor, lets say, works in clay and there are machines (analog or digital) to transfer this to a marble. In most cases results are ridiculous because of… you guessed it, similar to sss effect. When sculpting directly on marble, there we have a real time preview (view lol). I’m trying to say that, as we can’t have real time SSS preview when sculpting, maybe the use of displacement maps could help, as its adjustable. Similar with flesh textures I’m afraid. SSS can produce interesting effects but what if precision is what we’re after?
In any case thanks, I really appreciate this.