Uneven shading in render but not preview (Cycles) I am working on an animation of a product in blender using the Cycles renderer. The preview looks good, but the render shows uneven shading in an area. The only reason I can figure for that area looking different is there are a lot of very small polygons together. That being said, I don't know why the preview wouldn't show an issue.

What setting(s) could cause this kind of behavior?

EDIT: Solution

For future reference, I selected the problematic polygons using the Select Flat Face tool and then used the Remove Doubles tool. I tweaked the tolerance to keep sufficient detail and remove unneeded complexity.

Thank you to LukeD!



I'm sorry I can't release the blend file because it includes design files that will not be made public.

I have checked and doublechecked that the "Viewport Visibility" and "Restrict Render" settings are the same for all the objects. I have reproduced the problem at multiple resolutions and number of samples.

Here are the render settings.



Thank you for your help.
I've had this problem couple of times. I can't find in Blender manual anything about differences between preview and render but as far as I saw it preview isn't accurate like the final render.

In your case clearly geometry causes this shading (as in mine cases). For me only solution was to clean it up.

First of all try to remove doubles but if you want to make it 100% right you will need to retopologize this model.