transparency (maybe) Issues with karma

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I have serveral pieces of geometry that make up a screen:
  1. the body - (plastic like material)
  2. a plane piece that is the LED screen - (emissive material)
  3. and a piece representing a glass covering over the screen (for reflections and such) - (transparent material)

I've uploaded images from both the karma and redshift render.

When I render in Karma, the emissive mat is weird and it seems as if I'm seeing through the emissive material to the geometry behind it (circled red in the karma image). I'm using USD preview material but I also tried with Mtlx and it's the same. I then used both redshift and arnold to render the geometry with the usd preview surface and it works as expected.

Anyone experienced with karma can share what the problem might be here would be much appreciated. Thanks in advance.

Attachments:
karma_render.jpg (250.1 KB)
rs_render.jpg (195.7 KB)

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That's strange. the only thing I can think of is it a ray bias issue? The transparent layer between the camera and the emissive material, is it closer to the transparent material than the size of the ray bias? (default is 0.001 for Karma and Mantra I think) For small objects modeled in meters, the default may be a tad large.
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jsmack
That's strange. the only thing I can think of is it a ray bias issue? The transparent layer between the camera and the emissive material, is it closer to the transparent material than the size of the ray bias? (default is 0.001 for Karma and Mantra I think) For small objects modeled in meters, the default may be a tad large.
Yes! that was the issue indeed. thanks a ton. Also, what would be your recommendations (videos, articles etc) for learning karma more in-depth?
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traileverse
Yes! that was the issue indeed. thanks a ton. Also, what would be your recommendations (videos, articles etc) for learning karma more in-depth?

I don't know any other than the docs. I mostly use the scientific method of trial and error.
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traileverse
Yes! that was the issue indeed. thanks a ton. Also, what would be your recommendations (videos, articles etc) for learning karma more in-depth?

I don't know any other than the docs. I mostly use the scientific method of trial and error.
Docs are always best of course. I know they working on making the karma sections more comprehensive and polished so I'll stick with it.
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