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View Full Version : HELP- Global Illumination Lighting- Grainy/Noise textures, why???

wnschnapp
10-31-2008, 12:47 AM
Hi,

I am rendering a Maya 2008 scene in mentalray with GI and Final Gathering. There are 3 lights (2 Points, 1 Spot). One inside the room as the ceiling light, and two outside- one as the sun (Spot) with the mental ray "Area Light:Sphere" option on, and another to light the Outdoors picture plane. The point outside is only light linked to the Outdoors picture plane. Only the Point inside and spot outside are emitting photons and ray traced shadows.

--- I am getting weird grainy/noise on my textures (see picture in link). I am pretty sure this is from the GI with the outside spot/maybe the mental ray "Area Light:Sphere" option, but i don't know what i need to do to fix it. My scene size is very small so i dont have to emit an enormous amount of photons (before i was getting spots on the wall with a larger scene size). My GI on both lights is set to the default values-

intensity- 8000
# of photons- 10000
etc.

I DID change the values in the renderglobals. they were originally Mental Ray-Production and i changed the GI and Final Gather Accuracy to 250.

Please take a look at the picture and see if you can help me out.

http://www.rpi.edu/~schnaw/CG%20SOCIETY%20HELP%20.jpg (http://www.rpi.edu/%7Eschnaw/CG%20SOCIETY%20HELP%20.jpg)

Thanks,
Noah
phix314
10-31-2008, 03:22 AM
This looks to be a sampling quality issue. Whats the sampling quality on your shader/entire scene?
wnschnapp
10-31-2008, 05:35 AM
By Shader, do you mean the Mac Material?- The mental ray Attributes of the Macbook Base color Grey are default and the photon attributes are "derive from maya". What do you mean the sampling quality? of the light, or rendering globals? ....


.. Sorry, rendering in GI and FG is new to me.

I'm posting my scene file .mb on my site (link below). Textures with pictures are missing obviously. but you should be able to see the settings of shaders/lights/and render globals.

scene file is called "Cut 02 (DormRoom).mb". right-click and save- it's 17.5mb.

http://www.rpi.edu/~schnaw/

Btw, thanks for the quick reply.
Noah
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10-31-2008, 05:35 AM
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