I am building a city scene and just started putting in lights. I noticed that in a few areas there are artifacts occurring. I am pretty sure they are related to the geometry itself. The models have a very clean good mesh, but for some reason I am getting these artifacts ONLY when the scene is lit. Doesn’t occur with Occlusion or Maya Default Lighting. If anyone can help that would awesome! Thanks in advance.

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How are you lighting your scene? Using any GI/FG?
Have you tried adjusting the sampling settings of your lights?

n8skow [FA]

I am just using a directional light, spot light, and a point light. Only one has depth map shadows on. I have raytracing enabled. And I am not using FG or GI. No I haven’t how do I adjust them? Thanks!

Are you rendering with MayaSoftwareRender or MentalRay?
Have you changed the render quality preset in the render globals to ‘production quality’ or is it still on ‘draft’?

With depth-map shadows - you need to adjust the ‘filter size’ and ‘bias’ to get the desired shadow quality.

n8skow [FA]

Rendering with Mental Ray. The Quality is on custom. I’ve put the anti-aliasing sample settings up to min 0 , max 4. Well I switched over to Raytracing shadows and I’m still getting them. I have tried applying different shaders to the objects affected, but the artifacts still show up. It takes extremely long to render the areas with artifacts, if they helps to know.

Can you post the scene file to see if others are getting the same problem?

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Do you have any bump mapping or displacment maps on those objects?
As Longboarder1 suggested, are you able to post the scene files? Might be quicker tracking down what’s going on here…

n8skow [FA]

No I do not. But I do have a displacement map on a completely separate object.... Well the file is huge, like 800 mb. I am sure I can cut some stuff out to make it smaller, but first I am going to try switching up some settings. I am not a Mental Ray master, so I am doing some research and hopefully I can get some progress… Thanks for you’re help, I’ll let you know if I can figure it out.

800MB?
Is that including texture maps or just the scene file itself?

n8skow [FA]

Well its a big scene, everything is smoothed previewed… there are very little textures and lights, just lots of polygons.... haha yeah I know, 800MB! Well I figured out that it was the displacement map that was causing it. It was for the water below. I know nothing about displacement maps, and was just following a tutorial I found on how to make water… I work on a Mac and load my file into Boot Camp with Vista to render, and apparently the Vista Maya just didn’t like my Mac Maya File, so I just recreated the displacement map and it is all good. My lights were even not casting shadows so I had to recreate them also. Well thanks for you’re help!

glad you were able to figure it out klazer…
=o)

n8skow [FA]