"Fixed" Normals have noise

jesselarson

When I bake normals, there's artifacts that show up and I get rid of them by changing Normal mixing to Replace, adding a Fill, adding my baked normal map to the normal channel of that fill (with all other channels off) and then adding a white mask and paint layer to that fill and painting out the artifacts. I export the map using a preset with Normal DirectX (rgb). When I bring that exported map back in, I get a uniform noise across my model especially noticeable on reflective surfaces.

Here's some picture reference:
Normals with artifacts and smooth reflective surfaces

"Fixed" Normals with noise


What causes this and how can I fix it so that my normals are smooth?

jesselarson

Did some more testing and figured it out. Substance by default uses 16 bit to display the normal map. I was exporting at 8. Exporting a 16 bit png fixed the noise issue.