A SCREEN IS CONSIDERED by most home entertainment enthusiasts to be the eye-candy of a home theater, and right- fully so. You’ll be looking at it for hours on end, so it needs to be pretty, meaning it should have the qualities that allow a pro- jected image to appear bright, crisp and lifelike. Screens vary by size, shape and other characteristics—all chief considerations when choosing one for your home theater space. Remember, though, that certain qualities of your video projector—bright- ness, throw distance and black level—will dictate the size and style of screen that’ll work best in your home theater.
Screens for projection systems generally start at about 92 inches (measured diagonally). Because TVs now go up to 90 inches (and a few even larger than that), there’s really little reason to install a projection screen smaller than 92 inches. Size is what adds the drama to a home theater, so in most cases, bigger is go- ing to be better. Many home theater designers specify a screen size based on the ideal field of view for a given seating position. THX recommends determining your screen size by starting with your seating distance—simply multiply the distance by .84. For example, for a 10-foot seating distance (120 inches) THX would recommend a 100-inch screen (120 x .84 = 100.8).
Screens typically come in two shapes, expressed in width-to- height ratios. The first is a copy of the shape of your HDTV— 16:9. The second is much wider, made to naturally accommodate wide CinemaScope movies—2.35:1. Both screen shapes come with compromises, and your viewing habits, room size and bud- get will be part of your decision. If you opt for a 16:9 screen, all CinemaScope movies will have black bars on top and bot- tom, but House of Cards will fit perfectly. If you select a 2.35:1 screen, you’ll see black bars on the sides when watching HDTV, but ultra-wide movies will be awesome. Screen masking systems and specialized projector lenses can be used to accommodate all content sizes and screen shapes. A few movies actually switch between aspect ratios throughout the film.
Screens are made of a variety of materials and surfaces, and most of the differences are related to the screen’s gain, or how much light from the projector the screen will reflect back to you, the viewer. Screen gain is often made both more and less complicated than it needs to be. Basically, screens with positive gain (such as 1.3 in Stewart’s StudioTek 130) will reflect 30 percent more light as a matte white surface. A screen with a 2.0 gain will reflect twice as much light as a matte white board. This doesn’t mean you should always pick a high-gain screen. Higher gain typically results in hot spotting (where the image looks brighter in the center than toward the edges). High-gain screens may also reflect some colors better than others, depend- ing on the material. Some screens, particularly gray screens designed to optimize the image in bright rooms, actually have a negative gain. For instance, a .8 gain screen is 20 percent less reflective than a matte white 1.0 gain screen. Low-gain screens are often used to make blacks look darker when viewed with some lights on and when matched with a projector bright enough to make up for the dark screen.
In many custom home theaters the speakers are completely hidden, even the ones at the front of the room. An effective way to conceal the front three surround-sound speakers is to place them behind an acoustically transparent projection screen. Acoustically transparent screens can be either woven or perforated. Woven screen styles avoid the occasional moiré effect that can be caused by screen perforation overlapping the pixel grid of a projector.
Because the speakers are hidden, an acoustically transparent screen also gives you the freedom to easily place the speakers at the ear level of the home theater audience. Action taking place on the screen will more accurately sound like it’s coming from the screen.
Over the past few years a new trend in home theater has emerged, the light-rejecting screen. This type of screen is designed for use in media rooms where you expect there to always be some ambient light. If you have windows or room lights that would otherwise wash out a projection image, a light-rejection screen may be the solution. When paired with a bright projector, they can look impressive in any lighting condition. The optical properties of a light-rejection screen will reflect light coming from the direction of the projector, but not light coming from other directions.
Just because you selected a highly-rated screen and an excellent projector doesn’t mean that the picture will be perfect. The screen is a static piece of technology. It can’t be tweaked like other electronic components to compensate for throw distance, ambient light, wall and ceiling color (yes, both can be very important) and the light and color qualities of the projector. To get the best performance out of your screen, you will need to calibrate the projector to match the screen and room conditions. An ISF (Imaging Science Foundation) or THX technician can measure various parameters of your image and adjust the projector to ensure that the picture on your screen looks as perfect as possible.
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