PDA

View Full Version : SSS problem?


pzdm
04-08-2005, 02:29 PM
Hi there

I have next problem. I want to test SSS effect. So, I have used some older scene, three round lights. First is behind head, at a cross, this light is very intensive and colour of this light is yellow-orange. Second light is round too, it is located left over head and it´s blue with poor brightness. Third light is located right a bit under head, it is middle intensive and colour is yellow-orange. Every light has a soft shadow.

I have used SSS shader in Luminosity channel in Fusion shader with Fresnel. Everything is fine, but there is under nose some darker artifact. This artifact is emitted by third light. If I reduce Scattering Length, than is this artifact smaller. All normals are OK (they are point out). Model is in mouth area closed.

Have you got any solution for me?

Thank you!



PS: I know that my english is a bit rusty :-)

http://www.digitalmedia.cz/temp/test2.jpg

LucentDreams
04-08-2005, 04:48 PM
you not goign to like my answer;)

Welcome to the world of cinema 4D's very limited SSS shader. it is capale of beautiful results in very limited situations but has a lot of flaws in its design, this one being the key one you will run into. SSS creates a sort of transparent effect the larger is scatter and the deeper its absorbtion, this allos objects inside of polygons inside to be seen when they shouldn't be seen at all. only way to get around it is to lower settings a lot, or to remove that areas form the SSS using a vertex map and the vertex map shader.

JamesMK
04-08-2005, 05:04 PM
It is indeed tricky to get C4D SSS to look good. One thing (as also indicated by Kai) is to mask the problematic parts.... what I've done recently is to paint a vertex map with a value of 0% for the parts that just won't work ( mostly nose and eyelids has given me problems) and use it as a multiplier for the SSS shader. It is fully possible to get decent results, but it takes quite a lot of extra effort.

Uncle-Ox
04-09-2005, 12:10 AM
Hi

I tried using the SSS shader and the situation I ended up with, was that from 1 angle it would look awesome and from another it looked horrible. I just couldn't manage to get it to work from all angles. In addition to this problem, the rendering times are somewhat extreme which makes tweaking it a real pain in the butt.

I highly recommend you try faking SSS results with the Translucent Pro (http://www.vreel-3d.de/plugins/Translucent_Doku/links.html) plug-in. It's very easy to get good looking results with it, at MUCH shorter rendering times and best of all, it's very cheap.

Just keep in mind that none of the light-emitting shaders such as Translucent Pro and SSS, works with Global Illumination (to my knowledge).

ThirdEye
04-09-2005, 09:06 AM
The best SSS we have is Vreel Skin.

robodesign
04-09-2005, 09:54 AM
The SSS implementation in C4D is a joke, in my humble opinion :).

ThirdEye
04-09-2005, 10:03 AM
The SSS implementation in C4D is a joke, in my humble opinion :).

no it's not, because it doesn't make me laugh ;)

JamesMK
04-09-2005, 10:25 AM
no it's not, because it doesn't make me laugh ;)
Are you sure about that?

http://www.cgnetworks.com/challenge/entries/9/6028/6028_1112315473_medium.jpg (http://www.cgnetworks.com/challenge/entries/9/6028/6028_1112315473_large.jpg)

ThirdEye
04-09-2005, 11:25 AM
rotflmao!!

pzdm
04-09-2005, 12:50 PM
you not goign to like my answer;)

Welcome to the world of cinema 4D's very limited SSS shader. it is capale of beautiful results in very limited situations but has a lot of flaws in its design, this one being the key one you will run into. SSS creates a sort of transparent effect the larger is scatter and the deeper its absorbtion, this allos objects inside of polygons inside to be seen when they shouldn't be seen at all. only way to get around it is to lower settings a lot, or to remove that areas form the SSS using a vertex map and the vertex map shader.

I like your answer :-)). Thank you, I will try your vertex map solution and I come back.

pzdm
04-15-2005, 05:59 AM
Hi there, I have used vertex map and artifact has been masked. Thank Kai Pedersen! This is result of this test...

Montségur
http://www.digitalmedia.cz/temp/test3.jpg

Theropoda
04-15-2005, 03:40 PM
hi!

i really like that image!
could you maybe tell us how you did the fire in his eyes? i'm really interested!

regards
günter

pzdm
04-16-2005, 08:17 AM
hi!

i really like that image!
could you maybe tell us how you did the fire in his eyes? i'm really interested!

regards
günter

These eyes has been created only by two visible lights with very intensive contrast in noise and very low brightness and Wavy turbulence. If you want send me any message and I will send you file with this eye.

CGTalk Moderation
04-16-2005, 08:17 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.