Actually, there is no keystoneing in the image itself. I have it ceiling mounted and set-up without doing any keystone correction. The keystoneing you are seeing is from the camera location of the photos. I took the 'Mr. Freeze' picture standing up, and slightly off axis. Notice it is keystoned the other direction and I moved, oops. So I took the others with camera on seat. Not burry, but you get that view from lower then normal. I have the projector (Sony VPL-VW10HT) on 'light saving' mode which is less brightness, longer bulb life, and slower (quieter) fan. I believe the output with this setting is 700 lumens (Not positive, correct me if I'm wrong) So, I don't think a gray screen will make your image too dark Huey. You might want to experiment.