The video below explains the benefits of a DT Dynamic Masking Projector screen to overcome this.
How image contrast is improved with a Masking Screen
Changes in the projected image aspect ratio create low-contrast borders between the screen and the projected image. (in effect the image does not fill the screen and leaves white areas on the screen where the image is not projected. DT Dynamic Masking adjusts to match any possible aspect ratio using Mask Position Logic, restoring high contrast levels.
