View Full Version : SSS-Trouble

06-25-2007, 08:57 AM
Hi there,

its been a while since I posted here, but with Lightwaves new Nodes its about time to be frustrated again. :D

I am up to build a classic shot of a waterbottle (Plastic or PET).
The bottle itself isnt a problem, and it shines in its diellectric beauty, but the lid (blue plastic) drives me mad.

Thought of using the sigma-material for it to give ist a nice SSS-look.
I am well aware that this material only works with double-sided Polys.
I am getting exspected results when the lid is not "thickened" (only one side no "Box").
But when i start "thickening" the lid in modeller everything screwes up. I aint see any SSS at all. Even when I put the "Distance" to about 1 meter.8~

I will add some pictures of the two geometries if needed.

Thanks in advance


06-25-2007, 09:22 AM
Just 2 pics of the geometry.:)

Thomas M.
06-25-2007, 09:30 AM
Schwer zu sagen. Deine Bilder helfen da herzlich wenig. Vielleicht probierst du es mal mit dem Sigma Video was gerade gepostet wurde.

Viel Erfolg!

06-25-2007, 09:34 AM
Schon angeschaut und nachgebaut. Da ist alles np. ^^

Wie gesagt, sobald ich der Geometrie eine Dicke im Modell gebe, sehe ich absolut Null SSS.

06-25-2007, 11:18 AM
say what?!!!

06-25-2007, 11:36 AM
Just told Thomas that I ve checked out the Sigma-Tutorial before posting.
Everything worked fine there, but not in my scene. :D

Testing the Omega-Shader now which seems to do a flawless job so far. ^^

06-25-2007, 12:01 PM
Yepp, its basically the shape of a bottleneck.
Matched the lid to the neck and it seems to work so far, but I am getting problems with the top cause its not matching to the bottlesurface.

This makes thing a little more clear now.Praise the holy banana. :bowdown:

Using Omega atm, which seems to be the better choice.The first renders are a little distorted which should be fixed soon. :D

Gonna be a long night in the office, will get some :beerchug:

06-26-2007, 06:00 AM
Hehe, checked out Werners thread in the "work in progress" section. Veeery nice stuff!
Tons of usefull information concerning the omega-shader.

Thomas M.
06-26-2007, 06:20 AM
I strongly advice you not to use the Omega shader. It doesn't work correctly with radiosity. Sigma or Kappa (chanlum too) are the way to go.

06-26-2007, 09:54 AM
Due to the fact that the rest of the shot contains realflow-elements, radiosity is not an option. :p

Omega works fine for me, but the rendertimes hurt.
Gonna give it a try with the Kappa-shader.

Am I right that the Kappa II node is nothing else than two Kappa-nodes (one forward and the other one backward) connected?

Havent tested this yet....any suggestions?



Thomas M.
06-26-2007, 02:09 PM
Unfortunately not. Kappa II's radiosity is broken as it doesn't take the surface color into account, but uses white or a very bright grey as the color. Use just a backround image to light your Kappa II object and you'll see that your color map isn't there anymore. I don't have a clue what takes NT so long to fix this. Embarassing! (Case: 5210)

Thomas M.
06-26-2007, 03:47 PM
Right, that's what it SHOULD do.