# In depth guides and tutorials for Blender Cycles SSS and Hair BSDF?

Hi All,
The title posts my question…

Though this are recent features to blender cycles, I can’t find any in depth guides on this anywhere…

Cheers

SSS descriprion is not that in depth. Keep in mind Color is the surface color, Radius is the scattering color, Scale is the amount of scattering in real units:

Use viewport rendering to experiment and watch instantly what you’re modifying, and if you have more specific problems you may want to post here.

Hi margoG_ita,

Thanks alot on the quick reply =)

That info you just told me: “Scale is the amount of scattering in real units” is not in the blender wiki the “real units” part, I didn’t know it was refering to real units there…

The other one is just a reference to the section of cycles hair rendering in paricle system, not te Hair shader that was added to Cycles…

Once again, thanks

About Scale: 1 blender unit = 1 meter. (I use metric system) don’t know how works with Imperial, never tested.

Scale is actually multiplied by the Radius then, so if you use Scale = 1.0 and Radius = 0.1, 0.1, 0.1 is equal to Scale = 0.1 Radius = 1.0,1.0,1.0

When using colors it’s the same but calcs are not that quick, at least for me.

Let’s say we want the monkey to sub-surface scatter a bit of red like my example above. Setting Scale = 0.1 And Radius = .5, .05, .05 (RGB!) will give the same output as Scale = 1.0 and Radius = .05, .005, .005 (as you see i divided by 10 the Radius values to compensate the Scale being 10 time bigger)

Pluggin a RGB node into Radius is the same as entering the same values in the RGB dropdown (with the color node is much quicker and you have a feedback in the node editor)

About Hair: sorry i misunderstood you wanted shaders info. Use the different components (Transmission and Reflection) mix them together. I will post an example later, no time now sorry.

Thanks alot for that explanation ! Helped me understand it better.

cheers

I’d say more specific questions will help, i doubt a user will write a complete manual chapter about SSS and Hair because you ask for an in depth guide in a support forum (could happen though, but not sure at all)

Post what’s your problem, your goal, or what you don’t understand and someone will help.

By the way Blender Cookie has some nice tut. Haven’t checked for myself, i’m not a citizen member.

For Hair i personally use add shader with Transmission+Reflection, than another reflection layer…be sure to not use big values in Add shaders otherwise you will break energy conservation and introduce strong noise.

If you could please explain the roughness values on the U and the V… Those are the ones that are getting me the most worked up about

Cheers! And thanks alot for the reply

I also don’t quite understand the whole difference between reflection and transmission in the shader…

The problem with both this shaders is that there is no in-depth tutorial on any of them… Only the citizen one by Kent Trammell… and I ain’t a citizen member for now…

I think it is kinda sad that blender’s team doesn’t have any 1 doing in-depth tutorials (not necessarely video) for blender’s different options like the cycles shaders etc…

you can watch the light path tutorial by Bartek Skorupa.
He may be explaining the light path node,but he aswell explains the difference between most shader types.
in short, think of reflection like what happens in a mirror, and transmission like glass and other transparent type surfaces.
refraction bounces light and transmission let’s light pass through it’s surface.

Light Path Tutorial

Thanks alot Entity.

Will surely watch that tutorial!