Projection Screen 101 Winnipeg MB
Projection Screen 101
August 22, 2008 By Geoffrey Morrison
Projection screens are often overlooked, despite being looked at. Whether you're looking for a motorized screen or fixed screen, gray or white, matching your projector with the right screen can improve its performance, and perhaps the performance of your entire theater.
What's in a screen?
First and foremost, a screen reflects the light from the projector. The perfect screen would reflect all of the light from the projector, block light from the room, and create a perfectly uniform viewing surface. While some screens can do an admirable job at one or two of these, none can do all.
Some screens will focus the light more towards the seating area, but if you go too far, the center of the screen will appear brighter than the rest, and people sitting "off-axis" (as in, not directly in front of the screen) will get odd hot spots to the image. Some screens can block ambient light, but not perfectly, and these often add artifacts of their own. The goal is to find the best compromise that fits your viewing needs.
Now why wouldn’t you just want to paint your wall white? Get close to your wall, and you'll see. No matter what kind of paint you get, you just won't be able to make that surface perfectly smooth. At worst, you'll see this texture when you're watching movies. At best it can create odd reflection spots. And really, if you've spent several thousand on a projector, why not spend a little more for a decent screen to view it on?
The two most basic types of screens are drop down (retractable) and fixed. Retractable screens require more elaborate installation, but offer a huge "wow" factor as your screen drops down from its hidden cove in the ceiling. This setup also allows for a flat-screen TV to be used as a daytime display, with the screen coming down in front of it for nighttime movies. Fixed screens are, well, fixed. They come with a lightweight frame, and can just be hung on a wall or stood on simple stands (often supplied).
With single chip DLPs, LCDs, and the popular LCOS projectors, a 16x9 screen of 130-inches is probably the upper limit for a decently bright image. There are certainly exceptions (some can go bigger, some can't even go that big). Best to talk with your installer to find out how large a screen the projector you have in mind can fill. Keep in mind that light decreases with screen area, so a 120-inch diagonal screen is not 20% bigger (and therefore 20% dimmer) than a 100-inch screen, but is actually 44% larger, and 44% dimmer (all else being equal).
Three chip DLP projectors are significantly brighter, and therefore can have much larger screens. You can offset some of the light lost with larger screens with a higher screen gain.
Screen gain is probably the most quoted statistic. In the days of dark CRTs, this was extremely important. Now, most projectors can brightly fill most screen s...