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hello,

i am looking for create an sss material with a "diffuse material" not with a "specular material".
Is it possible or not ?
Because when i create a diffuse material which has transmission value and absorbtion medium in medium channel nothing happen.
someboby can show me with a project or explain to me exactly what i have to do ?

thank you guys

Wondering about this as well...

Hi,
Yes, of course it's possible.

1/ You need to use DirectLighting > GI_DIFFUSE or PathTracing/PMC.
2/ For a better result, you need a closed mesh. SSS material on open mesh will be treaten as infinite at the rear of polygons opposite to the camera by Octane. Usefull with a plane for fake local smoke, fog, etc. Semi closed objects will be wrong on the limits/borders.
3/ If you have a white color in Diffuse port, you'll see nothing because all light will be bounced/reflected (i don't know how to say that in english). The color you use in Diffuse will react with SSS too. A dark color or black is the easier way to begin.
4/ As you already know, you need to connect a node to the transmission or to add a color that's not black (to let light enter in the material).
5/ The density of the SSS is in global unit then, if you reduce or increase the size of your mesh, you'll have to adapt at least the density parameter.
6/ Absorption or Scattering medium need the same setup. Absoption is simply faster to render with less parameters.

Here three samples of Scattering and Absorption mediums
I hope this will usefull.

je n'y arrive pas ca ne marche pas.
Tu peux m'envoyer ton proojet steplait merci. ok pour le channel diffusse, ok pour le channel transmission. mais putain je branle quoi dans le channel medium. ca ne marche que dalle avec ce diffuse material. avec le specular material pas de soucis. mais la paye ta galère.

Bonjour guigui441987,

Voici un fichier d'exemple vite fait. As-tu vérifié ton kernel ? Seuls les DL GI_DIFFUSE, Pathtracing et PMC fonctionnent avec du SSS.
Si tu veux plus d'infos, j'ai écrit un petit article sur le sujet : http://www.atome451.be/subsurface-scatt ... ss-octane/

Here a quick sample file. Did you verified your kernel? SSS works only with DL GI_DIFFUSE, Pathtracing and PMC.
If you want more information, i've writen a little article about SSS (in French): http://www.atome451.be/subsurface-scatt ... ss-octane/

merci beaucoup atome 451 super ton site d'ailleurs il y a plein de truc sur lesquel je me posait des questions et du coup j'ai la réponse sur ton site.

Thank you very much for your very helpful SSS tutorial in your site, excellent blog.

Diego

Thanks guigui1987 and DieGolum. Glad to read my articles are usefull to someone.