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Bonsai
08-01-2003, 11:48 AM
Hi Folks,

has anyone ever tried to bake shadows with MR ? I´ve encountered some strange things yesterday. Before i start i have to admit that i am not the MR pro i would like to be so my questions concerning my problem are hopefully worth answering :)

First of all to my scene setup. More or Less LowPoly ( ~ 50k ).
Lightend with 2 directional lights, Final Gather is on.

Now to my problems:

Where do these strange artifacts ( the top red circle ) come from ?
How can i get the shadow to be more gradient ( right red circle )
Where does this strange PS Mosaic Filter like Effect come from ? (Lower left red circle )

The shadow in the green circle is fine. Comes from Geometry.

Here is the pic:

http://www.shoosh.de/bonsai/WWand.jpg


Hope you can help me out. Thanks in advance

Cheers
Bonsai
fiercekitten
08-01-2003, 05:11 PM
I am not sure about this, but it looks something I had in my renders when using caustics. Check in your render globals to make sure the caustics are off.
Bonsai
08-01-2003, 06:44 PM
Thanks 4 the answer, but caustics aure disabled ...
trthing
08-01-2003, 06:52 PM
Yeah, those round shapes look a lot like the photons you see in a badly adjusted caustic render...
:hmm:
gmask
08-01-2003, 09:01 PM
You need to increase the number of emitted photons from your photon emitter
mFlux
08-02-2003, 10:16 AM
Well I dunno but fiercekitten helped me figure this out. With Maya Mental Ray GI and Caustics turned on, and a low photon amount (ie 1000), you get ugly circle patches.

Check again if you're actually using caustics/GI or using FG.
gmask
08-02-2003, 05:50 PM
Originally posted by mFlux
Well I dunno but fiercekitten helped me figure this out. With Maya Mental Ray GI and Caustics turned on, and a low photon amount (ie 1000), you get ugly circle patches.

Check again if you're actually using caustics/GI or using FG.

When using caustics you need to increase the number of caustic photons.. a setting of 500000 will produce very smooth resutls whereas a setting of 1000 produces spots. You may not notice it as much in a still but low settings for photons for other functions of MR like GI and FG will cause the same spottyness.
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