Explanation of Sub Surface Scattering?

[ngrava]

I know I've been requested this for a while and I'm sorry if it's getting annoying, but it's time now. I really, really need some explanation of how the translucency controls work.... Please. Just a simple explanation. I don't need a whole tutorial full of pictures or anything. The main issue is that now that the algorithm has changed, nothing seems to work like it used to at all. I just need a simple road map so I can get back to where I used to be.

Thanks!

-=GB=-

[percydaman]

i thought vlado said there will be some upcoming info on that subject... guess we'll just have to be patient.

[ngrava]

Yep. I remember. I'm just up against a wall and need some simple explanations.

-=GB=-

[vlado]

It will help if you describe what effect you are trying to achieve (e.g. skin or wax or cheese or something else).

Best regards,
Vlado

[flipside]

I'm trying to achieve the effect on fake blue ice cubes like this material:



But then for smaller cubes/spheres.

[ngrava]

Sure. I'm trying to make translucent flower peddles. The under side needs to seem as if it's receiving illumination from the top. What is happening is that they are simply dark like as if there was no translucency. The way I would have achieved this before is to:

1.) High translucent value.
2.) Medium transparency(IOR) with 0.2 refraction blur.
3.) Thickness set for 10 cm. Doesn't seem to change anything when set to high or low values.
4.) Light mult. set to 5. Again, does not seem to effect anything.
5.) Scatter mult set anywhere from 0 to 1 doesn't change anything. should be set at 0.1 or 0.2 in order to get the light to scatter through it.
6.) Back/forwards scattering doesn't seem to change anything. it should be set at 0.0 to get back scattering.
7. Diffuse color is set to a pale pink.
8. same color in the fog multiplier. no effect when changing the value. This used to work.

The under side is either dark pink or dark black. I'm using Med Irradiance Map with Light Cache. Light Cache is set to calculate blurry effects.

I'll post some images soon.

-=GB=-

[DaForce]

Is this kind of what your after?


Is a very simple scene that i setup, basically a sphere with a leaf texture and its opacity map used for displacement and the water level set to cut of all the non displace mesh. So it just looks like a curved leaf.
With abit more tweaking and the proper environment i reckon it could be just what your after. As you can see the light is coming thru the leaf. Not all over it because it still needs some more tweaking but you can see how it works as it should

You can have the max file for it if you want.

[RErender]

Looks like everything except the leaf :P nice shader though

[DaForce]

"Looks like everything except the leaf"

Huh

[RErender]

It's been a long week but I swear I see a red sphere with a leaf cut out of it

[DaForce]

Well yeah pretty much.....but its been a long week for me too...and i cant work out what you meant by "Looks like everything except the leaf". makes no sense to me ATM

FYI the shader was the focus of my post not the leaf/sphere thingy.

[davision]

I was confused by the image too --- but I did know what he meant by "except the leaft" -- the dark blood red area looks to be in the shape of a leaf -- and it looks like it's missing.

After looking at it I see that the pinkish color (on the sphere) is actually the leaf surface (although the shape isn't apparent) and the blood red area is actually a hole revealing the inside of the sphere (or back side of the whacky looking leaf).

[DaForce]

Mmmmm Maybe this will help clear things up
www.apex.net.au/~daforce/vray/leaftest.avi

Its the shape of a leaf wrapped around a sphere.

[CCS]

I still don't understand how those teapots stay on there.

[RErender]

heheh, hmm guess what threw me off was " basically a sphere with a leaf texture" I understand that you cut it out with the opacity map but why have a leaf texture if you are discarding the leaf? For your example I don't understand why you kept the sphere but not the leaf, make sense? Anyways the shader is the focus like you said.