16/9-Format Test Pattern
This test pattern consists of a circle in the center and four smaller circles located in the four corners of the screen. It's used to assess the proportional transformation of the image in 16/9 aspect ratio. The circles must be truly round. If they're not, then the projected images will be distorted.
4/3-Format Test Pattern
Again, this pattern consists of a circle in the center and four smaller circles in the corners. It assesses the proportional transformation of the screen in 4/3 format. The circles must be truly round. If not, the screen will show distorted images.
Once we've screened this series of test patterns, we then optimize the video projectors in order to show movies under conditions that are equivalent to what you'll have in your home after adjustment.