A normal map appears to be using input image with incorrect gamma. This can cause shading artifacts.

This message occurs when Corona detects that some of the CoronaNormal maps contain map with gamma set up incorrectly.

Normal Map - correct result:

Normal Map - incorrect result due to wrong gamma correction:


  • This can be easily automated for all materials in the scene using the Converter Script
  • Alternatively, you can perform a quick fix by enabling “Add gamma to input” checkbox in CoronaNormal map containing offending input
  • When loading bitmap file through the “Select Bitmap Image File” window, at the bottom part of the window, in Gamma section, click "override", and set its value to 1.0

See: How to use normal maps?