Hi there! I modeled a concave front panel for a video projector in Rhino 7, where it looks perfect in render mode. When I render it in KeyShot in high resolution (3400x2400 pixels) or in lower resolution it shows spots all over the surface, as if the model were not smooth. How can I eliminate them?
I use KeyShot for Solid Edge (a kind of bundle), and I exported the model in highest resolution from Solid Edge. There are no tessellation problems visible at the edges of objects, only this spotted surface bothers me.
I’m not really seeing what you are talking about with the spots, can you post another screenshot with them circled?
Either way, if the geometry is fine, then look at your lighting. Sometimes an HDR with not enough resolution can cause reflections to show the imperfections of the HDR.
Hello Matt! Thanks a lot for your feedback! The spots are evenly spread all over the surface. It looks a bit like if you wiped the surface with a dirty wet cloth. Regarding the lighting, I am working on it at the moment, I will take your advice as a good way to test it out.
Set a plane light. Now the surface looks fine, but I have artifacts where there are caustics (?) in the edge between the shiny black lens tube and the white plastic housing’s front panel. How can I get rid of these?
I’m not sure if they will be gone but you can try a bit of rounded corners on the objects. Makes the render also more realistic without the infinite sharp edges that catch no light.
Good idea! I’ll give it a try. Thanks!
Just to be sure, I don’t mean to change the model itself but just use the Keyshot function for those edges 
Oh! How can I do that?
Very easy in KeyShot and really helps a lot even if you do it a tiny bit, you give at least some surface to have reflections/light work on the edge. WIth default CAD/3D Model edge that’s not possible since they are like unlimited sharp.
Thanks! I’ll give it a try.
Edit: I tried it, but then even the smallest radius (0,001 m = 1 mm) looks too big on my object. I would have liked to have something like 0,25 mm. Is that possible?
Edit2: I found it: I can type in the dimension (0,00025 m), I don’t have to use the slider.
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Are you using caustic lighting setting in the render? The top part of the lens, those white spots look a lot like fireflies to me. Did you try the denoise > Firefly Filter in the Image tab to remove these?