What Filters Do In Maya

Filters basically smooth pixels. Whenever you create a file node in Maya, you'll have a filter type option.

By default, it's set to quadratic.

Download and open scene wall.mb

The perspective camera has been locked at an up-close shot of the wall. I have turned filtering off. When you render it, it looks rather pixely.

Now select the wall, go to the rendering shelf and click the wavy checkerboard icon.

This will open the attributes editor to the material that's assigned to the wall. Click the black arrow adjacent to the text Color (most average users already know that this'll take you to the node that's connected to the color. In our case, it's a file node.).

Under filter type, change it from off to quadratic. Now render it. The rendering looks much better now. The filter has smoothed off the pixels. Play with different filter types and notice the different results.

Pre-Filter

Continuing where we left off, let's check this attribute. Now when you render it, the wall texture seems to be blurrier. Now, the higher you set pre- filter radius attribute the more blurred your texture will appear. This can come in handy when you have a low resolution map and you don't want it to appear pixely.

When To Turn Filtering Off

The main time to turn the filter off is when the texture appears too blurry. An example of this is you have an image with text on it that you've assigned to a 3D model. Depending on the size of the text, it might be hard to read. So it's better to turn filtering off.