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nepaligurkha
11-12-2005, 07:04 AM
Hey,

I trying to use SSS for a lamp shade with misss_fast_simple in maya with mental ray. I noticed that the SSS dosn't work if i put the light inside of the lamp(using a point light). Has anyone else run into this problem? I researched about it, but i couldn't find anything about it. I was using lights outside of the lamp too, and i thought the SSS was working, but i then tried it with out the other lights and HDRI, i found out the light inside of the lamp wasn't doing anything. How have other people used SSS for lamp shades? Could someplease help me?

-Tabha

nepaligurkha
11-13-2005, 05:34 PM
come on, somebody must have used SSS for a lamp?

MoZz
11-13-2005, 06:16 PM
I think you need to give some thickness to your lamp geometry. Maybe.

Bye

protproto
11-13-2005, 09:24 PM
MoZz is right, you need volume for sss shaders. In the end of this thread I learned it myself.
http://forums.cgsociety.org/showthread.php?t=165670&page=2&pp=15&highlight=sss

jeremybirn
11-13-2005, 11:11 PM
come on, somebody must have used SSS for a lamp?

No reason to so far; translucence works for that!

-jeremy

nepaligurkha
11-14-2005, 12:55 AM
translucence, u mean a translucence map? I haven't worked with translucence maps before, i thought that translucence maps its only that the surface is either transparent or its solid right?
I want to achieve somthing like this ----> http://img385.imageshack.us/my.php?image=img23718jn.jpg can this be done through trans maps? I extruded the faces of the lamp and increased the thinkness, but the SSS still didn't work.

Thanks
-Tabha

jeremybirn
11-14-2005, 01:32 AM
Yes, something like that is plain translucence. You could map it if you want, but in the picture you provided it wouldn't need a map, just slide it up to .25 or so and adjust the decay of the light. The surface of the lampshade doesn't need any thickness, it's simpler without it.

-jeremy

nepaligurkha
11-14-2005, 02:18 AM
hey thanks man, it worked. The only thing is the lampshade is coming out really grainy (i don't know what word to use the describe it) here is the render----> http://img105.imageshack.us/my.php?image=transslent6vf.jpg
do u think it has somthing to do with the diffuse map? or with like the Translucence depth and focus settings?

thanks again
-Tabha

jeremybirn
11-14-2005, 02:44 AM
Nothing to do with your translucence. That's fine, you're done.

When you use an area light or give a light radius to a raytraced shadow, shadows get grainy until you turn up the number of shadow rays.

-j

nepaligurkha
11-14-2005, 04:00 AM
hey thanks again

-Tabha

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