I have had a somewhat similar problem on normal maps from substance painter where I will get polygonal banding in Blender even though the map seems to work fine in substance and on sketchfab. I’ve used both DirectX and OpenGL with the same result. The problem may not be related, so I hope you don’t mind me piggy-backing @ben-reynolds . I seem to always struggle with getting a clean normal map that behaves predictably, no matter what program I bake with, so I am all ears on this thread.
