Maya for 3D Printing - Rapid Prototyping
In this course we're going to look at something a little different, creating technically accurate 3D printed parts.
# 1 10-09-2014 , 06:34 PM
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Black pixels when using Mitchell or Lanczos

I'm getting this issue when I use Mitchell or Lanczos sample mode user added image

Even on surface shaders I get these black dots.

I only got rid of them by making a scene from scratch and importing the old scene into the new scene, however this is a less than ideal solution since I have to reapply all shaders. I want to know what causes this.

Another problem I'm having with the same scene (even the new/imported one) is all of the sudden the scene takes longer then normal to render, about 3 times what it should take even though it's just type with a HDR lookup sphere and a blurred version of it linked for final gather. Settings are what I normally use with no problems. The only "complicated" thing in the scene is reflection of the type. And even though it`s taking long I'm still getting unacceptable amount of noise. I'm new to mental ray but this type of stuff makes me think I should stick to vray. Hopefully some blessed soul can help me out here. user added image

# 2 10-09-2014 , 11:01 PM
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# 3 10-09-2014 , 11:27 PM
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They could be NAN artifacts and who knows how they're being generated. Could try :

- Run a clean up on the geometry if it's poly
- Export problem model as obj(and not a maya scene file) and import

Even though it seems like a geometry issue you could try:

- Disable any IBL and FG and test
- Even with IBL enabled, try a different HDRI and test


- Genny
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# 4 15-09-2014 , 02:08 PM
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exporting and importing as obj resolved issue, thank you user added image

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