Normal maps generated from Substance have poor compression quality.

Symptoms

• Normal maps within procedural materials (which are generated dynamically) are showing to have lost quality when compressed. 
• Substance Designer generated a new material with a normal map that had certain quality. When it was compressed in Unity, this same material changed quality. 

Cause

Substance Designer uses an image without compression to calculate the normal map. When the .SBAR file format is exported to Unity, it is saved with compression. Here the artefacts occur, since there is a loss of quality. 

Resolution

There are a couple of things you can try:

• Use a higher level of JPEG quality in the Bitmap's properties in Substance designer. 
• Use a method of compression that allows you to maintain the level of quality.  

More Information

This article applies to Unity versions 5.x