August 09, 2010
| by Arlen Schweiger
AV Science Forum poster DocPrego is an inspiration to any DIY theater enthusiast. He’s already on the third incarnation of his “Ridiculously Inexpensive Dedicated Kick-### Home Theater,” having recently gone from an 89-inch to 120-inch screen (the first incarnation was actually a room with an old 4:3 screen). One thing he’s realized with every version is that screen masking is key to maximizing projected images.
Masking involves covering the unused. dark gray, bars produced on the top and bottom of the screen when showing a movie whose aspect ratio is wider than the screen’s.
You’ll find that “CinemaScope” 2.35:1 or 2.40:1 aspect movies’ colors pop more and that the image generally seems sharper when the bars are masked to match a common 16:9 screen’s conventional black fabric border. Here’s how DocPrego achieved it in a “ridiculously inexpensive” manner for his 89-inch screen (you can read more about the masking solutions for the 89-incher here and the upgraded 120-inch screen theater here):
—He started by using leftover black velvet material from the screen he built.
—At Lowe’s he found a 2-by-8-foot sheet of sturdy foam (after looking at several flimsy types) to wrap in the fabric. “But how would I keep these masks in place?” DocPrego wondered. “My first thought was that it would be great if they fit inside my screen frame tightly by friction alone. I grabbed some Velcro just in case and then got a roll of masking tape to secure the velvet onto the foam, and a utility knife to cut the foam.”
—He got home and projected a 2.40:1 Blu-ray image onto the screen and measured the bars. They were about 5 inches tall, so he cut the masks to 5 1/4 by 77 3/4 inches (the inside width of the frame).
—He used masking tape to pull the velvet tightly around the foam and secured it to the back of the mask. A test fit proved the mask to be about a quarter of an inch too wide, so he opened the velvet and cut off a tiny amount of foam and recovered.
“It fit like a champ, and no Velcro was needed because the friction was more than enough to hold it in place,” he says. “How did it turn out? Amazing! I was giddy when I projected my first 2.40:1 movie on it. Beyond belief, the improvement that the masks made.”
Total cost? About $7.50 for the foam, $2.50 for the masking tape, $1.96 for the utility knife and the original cost of the velvet. “I guess I spent about $20 total including the velvet, but I think I am overestimating.”
Below are shots of the room courtesy of DocPrego. The darkened room pics have been tweaked for brightness and contrast to try to better show the masking (as he says, the giveaway in the non-masking image is the pause icon in the lower left corner from the Blu-ray disc).
Arlen writes about home technology installations and product news and reviews for electronichouse.com
and Electronic House magazine.