Ever wonder why your shading looks wrong in your viewport? Here's a quick tip to correct a normal map shading problem that you might see in the viewport in Maya 2018
If you made the switch to a newer version of Maya and loaded up an older asset, you may have noticed that something doesn't look right with your normals. Your object might look flat and doesn't take well to lighting - luckily there's a simple fix for this.
In Maya 2018, Maya's Viewport 2.0 is the default viewport. Viewport 2.0 is color managed by default. You may have heard of "linear workflow" which is part of a proper color managed pipeline. In this case, it applies both in the viewport and in your renderings. This means you'll get accurate color and much more realistic lighting directly in your viewport where you playblast.
With color management on Maya treats normal maps like any other image map, expecting them to be color. However normal maps aren't color, they describe how to shade a point on the surface to give the appearance of detail. If we treat normals maps as color data, we get incorrect shading.
In order to fix this, you can select the offending object: right-click and go to Material Attributes. Depending on your material, find where your normal map is connected and in the file texture node, set the Color space to Raw. This should solve it!
You can also automate this action in one click if your normal maps follow a naming convention. Open up the color management preferences, and add a rule: for example, any file format with *_nrm.* should be set to Raw. Hit re-apply and all your files are fixed. For more details on setting Color Management rules, please see this link.
Artwork by Paul Tosca. Check out his fantastic work here.
For more details on applying Color Management policy studio-wide, please see this link.