After doing some research, it seems that the most light reflected from a high power screen is on the ceiling and the wall directly behind the viewing area. I have darker beige walls and a white textured ceiling. Painting the ceiling black is not an option and just hanging fabric on the ceiling would probably sag and not look right. I found this self adhesive light absorbing fabric called "flocked light trap material" and ordered a roll. The size of the roll of material is 30" width x 500" length. The projector is mounted on the ceiling and when pulled down the screen surface is only about 8-9 inches from the ceiling. Now the width of the wall behind the seating area and ceiling is 150". How far should I extend this material out past the screen to get a majority of the benefit? Is there a certain distance where putting anymore material would produce minimal or no benefit? How about the back wall? The ceiling is 8' high and the projector is mounted about 50" off the ground. Does the whole back wall have to be black or can just part of it be?