Anatomy of a Projection Screen

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Credit: Stacey Poythress

Everything you need to know about screens, including masking, automation, size, and pricing.


Sep. 23, 2010 — by .(JavaScript must be enabled to view this email address)

If you’re looking to create a media experience that rivals the one you get at your local Cineplex, a projection screen is the way to go.

Paired with a video projector, they can display images in a format larger than any TV screen can. Plus, with extra features like masking, motorization and perforation, the screen will be able to adapt to any design or viewing preferences you might have.

Here’s a look at key features to consider when you’re shopping for projection screens.

Motorization, Masking
Fixed screens work well in dedicated theater rooms where it’s fine to keep a big portion of your wall covered at all times.

For multipurpose rooms, consider a retractable screen that disappears when it’s not in use, perhaps revealing a flat screen TV. Screens can retract from the ceiling, floor, wall or furniture.

In addition to raising and lowering a screen, motors often are used to adjust the width of the screen depending on the aspect ratio of the image. Masking the screen from side to side allows viewers to enjoy the full height and the full resolution of the video, without seeing those annoying black bars.

Three important considerations when selecting a motor for your screen are maintenance/longevity, loudness of the mechanism and ease of integration.

Automation
Motorized screens (up/down) and masking (left/right) can be controlled in a number of ways: infrared remote control; low-voltage wall switch; low-voltage trigger from a projector, receiver or other electronic device; or direct control via a home automation system.

Motorized screens are fairly easy to automate because they are usually in one of two states: completely up or completely down.

Side-to-side masking solutions can be more complicated to automate. A specialist can program your system to automatically mask your screen according to the content being played. The mask will stretch out for ultra-widescreen movies, glide inwards for boxier shows, and possibly close all the way when the theater empties.

Screen Material
For the best performance, select a screen material and color optimized for your specific projector and room conditions.

A matte white screen is typically the best choice for dark environments. In rooms where ambient light is a factor, a gray screen can be used to preserve contrast.

For the most realistic surround-sound experience, place the center speaker(s) behind the screen. This configuration requires an acoustically transparent screen that allows sound to penetrate the fabric via tiny perforations. Ideally, the speaker(s) should be placed about 12 inches behind the screen.

The “brightness” of a particular projector must be evaluated in the context of the screen size: The larger the projected image, the dimmer it will look given the brightness of a given projector, so plan accordingly.

An important characteristic of a screen is its gain, which measures how light reflects off the surface. In simple terms, a higher gain equates to a brighter image; however, a high-gain screen (above 1.3 or so) may limit the viewing angle and create sometimes an inconsistent quality across the entire screen. 

Brighter rooms may require a dramatic increase in brightness or contrast for an image to be enjoyable. It may be better to increase the “horsepower” (ANSI lumen output) of the projector rather than the black level and gain of the screen.

Screen Size
Consider these two things when specifying the size of the screen: the resolution of the image and its distance from the viewing area. The higher the resolution, the closer you can sit; the closer you sit, the smaller the screen should be.

For a 1080p image, a good rule of thumb is that the height of a screen should be about one-third the distance between the screen and the best seat in the house. For example, if your best seat is about 14 feet away, select a 16:9 (widescreen) that’s 54 inches high x 96 inches wide (110” diagonal).

Some home theater experts also use a rule of thumb based on the horizontal measure of the screen, suggesting that the distance between the screen and the seating should be about 1.2 times the width of the screen.

Screen Features
Many of the better home theater screens have tension tabs along the sides to keep them taut and flat.

A rear-projection system can be an excellent alternative when a room is too bright or the space simply cannot support a front-facing projector for whatever reason. Make sure you select a specially formulated screen for this application.

Larger and wider images have spawned a new class of screens for home theaters: curved screens. Because of the curvature, more of the light reflects into the seating area, rather than the walls of the theater. Curved screens also can create a more uniform image between the center and edges of the surface.

If the housing for your retractable screen is going to visible, there are several attractive options beyond harsh rectangular metal pieces found in conference rooms. Some even provide LED lighting so the housing can double as a sconce when the screen is not in use.

For screen maintenance, brush the surface softly with a clean, soft-bristled brush to remove any loose dirt or dust. Do not vacuum or use sharp instruments. For tougher spots, try a non-moisturizing/non-oily detergent (diluted to 20% strength), water, and a cellulose sponge.

Pricing a Screen
Typically, the price of a video screen depends on the size of the surface, the quality of the screen material, motorization and a handful of other features.

Screen Size
Naturally, the price of the screen increases with its size. A 92-inch fixed screen that is suitable for a home theater might retail for about $1,000 and a 110-inch piece might sell for about $1,500. Decent Internet brands and more mainstream screens might cost half that amount, and premium providers can easily double the amount. The aspect ratio (shape) of the screen (16:9, 2.35:1, etc.) does not really affect the price; generally, it’s the surface area that counts.

Motorization
Expect wide swings in the price of motorization for video screens. Be aware that it’s not just the motor you’re paying for. The screen design changes as well in order to maintain the shape and integrity of the material. Make sure your motorized screen has side supports to keep the surface taut. Adding motorization to a good screen can range from $500 to $2,500 depending on the quality, longevity, automation features and loudness of the motor, as well as special accommodations to the screen itself. You’ll pay much more, possibly three times the amount, for a screen that lifts from the bottom because it requires additional support. Side-to-side motorization for masking is two to three times more expensive than up/down motorization. Don’t forget to consider the extra cost for installation and integration.

Screen Material
Most elite manufacturers charge little or no premium for different colors and textures of screen material. The exception is for acoustically transparent screens that are perforated so that speakers can be situated behind them. Perforating the screens can be a highly scientific process. Expect to pay a 15 percent to 20 percent premium on the more modestly priced screens and up to 40 percent extra on higher-end models.

Additional Features
Some manufacturers make screens that are suitable for covered outdoor spaces. A weatherproof housing might add about 15 percent to a screen. Even in indoor spaces, screen housings can vary, with more aesthetically pleasing units coming with a 20 percent premium or so. Don’t forget to inquire about the cost of control, including special modules and controllers for automation.

Stewart Filmscreen contributed to this article.



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