Projection Screens

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What is a projection screen and what is it used for?

A projection screen is a large reflective surface, usually white, that’s typically hung on a wall in a room at some distance in front of any type of digital or film projector for the purposes of entertainment, training, education or a sales presentation. Compared to a bare wall, a projection screen affords higher reflectivity, resulting in a brighter picture. A screen also bestows a more uniform image surface and truer color rendition. Still, there are special paints that can be applied to a wall in lieu of a screen (see below).

Why choose a projection system?

If you’re buying a screen, you’re already sold on the dramatic advantages of a projection system: picture size that dwarfs almost any TV, scalability without necessarily buying new equipment and the elimination of overt letter-boxing or columns that TV viewers often find distracting when the program’s aspect ratio is different from the TV geometry. Also, when you combine the cost of screen and projector, you can’t beat the per-inch value of a projected picture compared to the biggest TV you can find.

What venues are served by projection screens?

Conference rooms, board rooms, classrooms, auditoriums and movie theaters are the most likely spaces to sport a permanent screen. But the leading locale is a room in a private home used as a home theater.  Given the variety of settings and applications, projection screens are available in a wide range of sizes and prices.

What’s the difference between a data/multimedia projector screen and a home-theater projection screen?

Not much. Since both types of projectors can be hooked up to a computer, Blu-ray Disc player, DVD player, games console or cable box, the screen doesn’t care what type of content is thrown at it. More important distinctions are made regarding screen size, aspect ratio, amount of reflectivity and how the screen fabric is stored when not in use.

Do you need a dedicated room where the projection screen will be deployed?

No, but if you’re fortunate enough to have a dedicated home theater room, a screen mounted to the wall or ceiling will serve your needs. Most people use a TV to watch movies, sports, TV shows, concerts and home videos or play video games and view slide shows. But when the occasion calls for it, why not widen the canvas, perhaps in the same room as the TV? Call it your multi-purpose room. When the projector isn’t being used, you should be able to hide the screen.

What is aspect ratio?

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Screen geometry is straightforward. You can buy a screen that is square (in which the width and height are 1:1), in the conventional TV and computer display format of 4:3, and in the HDTV format of 16:9. Wider screens are available, too. By today’s standards, square screens are kind of square. Business presentations are more likely to fit 4:3 parameters, especially if the video source is a computer. A digital camera’s default aspect ratio is 4:3 as well, but if you’re shooting pictures or video with a widescreen monitor or HDTV in mind, you probably changed to a wider setting. If you’re buying a screen for a home theater, you don’t want anything less than 16:9 to accommodate HDTV broadcasts and movies on Blu-ray Disc or DVD.  Theatrical movies can be wider still. When viewed on a 4:3 or 16:9 screen, such movies will often appear with black bars above and below the picture. The borders are referred to as letterboxing. On a fixed display such as a flat panel TV, the letterboxing is obvious; on a projection screen, not so much. The bottom line is that you’re better off today with a wide screen.

How big a screen do you want?

Home theater experts say a common entry point is a 100-inch diagonal on a 16:9 screen. Based on those measurements, the screen will be about 87 inches wide and 49 inches tall. Common sense dictates that the wall behind the screen needs to be at least 6-inches wider to accommodate the screen’s bezel and ceiling mount and the room height needs to be tall enough so that the screen’s bottom edge is at least 3- or 4-feet above the floor. That way, seated members of the audience can be more than one-person deep and still see the entire picture without obstructing anyone's view. In summary, before ordering a 100-inch screen, measure the destination wall to make sure it’s approximately 8-feet wide and 8-feet high. Sure, you can shave a few inches off both these dimensions, but it’s better to overestimate how much space you need to comfortably hang a screen and enjoy the results than trying to shoehorn too much screen into a tight space. If you do have the space, you may want to spring for a 120-inch diagonal. In that case, the screen itself will be about 102-inches wide, so your wall should be at least 9-feet wide in a room with at least an 8-foot ceiling.

How small a screen can you carry?

At the other end of the jumbo screen category is the takeaway tabletop screen. The smallest are meant for use with a pico projector and can be packed up as easily as a notebook computer. A popular choice is a screen with a 25-inch diagonal when unfolded. But larger screens that fold up like an accordion during transport are available, too.

What’s a tripod screen?

Easily stashed away in a broom closet when collapsed, these portable projection screens contain three legs that snap in place to support a screen that you manually extend like an inverted shade from its rolled-up base. Aspect ratios are available in square, 4:3 or 16:9 and diagonals range from about 60 to more than 100 inches. Setup takes seconds. Such screens can be used outside at night, but it better be a pretty still night since, without ballast, they can be toppled by a gust of wind.

Is the manufacturer talking width or diagonal?

Although the screen size of a TV is measured by the distance from the lower left to upper right corner of the visible picture—the diagonal—projector screen sizes are sometimes referred to by their widths. Make sure you and the sales person are in the same dimension when you’re deciding on screen size.

What is a drop-down screen?

The screen is rolled up and hidden in a compartment near the ceiling until you trigger an electric motor to lower it. This is a great option for a multi-purpose room, since you could still use a flat-screen TV for watching programs and the drop-down screen for viewing movies. Other ways to make the screen disappear is a manual screen that retracts by hand.  Alternatively, you can position a portable screen on its own three- or four-legged stand that you take down and set up as needed. (See “What’s a tripod screen?” above.) In the case of a screen permanently fixed to the wall, there’s also the option of a manual or motorized curtain for hiding the screen.

Is tension a good thing for a screen?

Manual screens may be tensioned or non-tensioned. Tensioned models attempt to keep the fabric flat and immobile, while non-tensioned models have the screen fabric hanging freely from their support structure and are likely to move if there’s a breeze from air-conditioning or people milling about, causing momentary imperfections in the projected image. So, tension is desirable. Otherwise, you may as well drape a bed sheet over a clothesline and watch it flap.

How white should the screen be?

A matte white finish is the default for projection screens. You know from picking up a glossy photo print that the alternative, a matte finish, is less likely to reflect unwanted light. But a surface exhibiting a light shade of gray may enhance the blacks of brightly-projected images in rooms that are not entirely dark. The assumption is that, if the projector is bright enough, whites will remain agreeably white while blacks will be perceived as blacker. The result is more contrast, which is why such models are referred to as high-contrast gray screens. If the room is really dark—including the furnishings—choose a white screen. But if the projector puts out a lot of light and the room either leaks ambient light or the furnishings reflect more light than you’d like, choosing a slightly gray screen may improve the viewing experience.

What is screen gain?

The material that a screen is made of determines the amount of reflectivity. High gain (more than 2.0) screens are useful when the projector isn’t very bright (as in a pico projector) or in rooms where there’s more ambient light than you’re able to shut out. Though high-gain screens brighten the image, they may do so by narrowing the optimal viewing angle and often at the expense of color purity, uniformity in brightness and resolution. A medium gain (1.1 – 2.0) screen can be moderately helpful in compensating for a less-than-robust projector. By choosing this type of screen, negative effects such as hot-spotting and a drop-off in off-axis viewing brightness are ameliorated. Low-gain (1.0) screens reflect light uniformly without the tendency of a high-gain screen to gather its reflective output toward the center of the viewing area. What’s good about a low-gain screen is that it will afford about the same brightness no matter where audience members are sitting.

Do you want a perforated screen?

Most screens aren’t meant to let sound through, since speakers are typically placed around the picture anyway. However, you can choose a screen that leaks acoustically. With a “perf” or weave screen, a center speaker (perhaps the left and right fronts as well) can be placed behind the screen. Thus, when actors speak, their voices would be coming directly through the micro perforations under their enlarged lips. In practice, a well-balanced external sound system makes such literal speaker placement unnecessary. Still, it’s cool to be able to press your ear against the screen and hear sound—just don’t do it while others are watching, though, because you’ll block the picture.

Is there a rear projection screen option?

As long as the projector is rear-projection capable and there is room behind the screen, you can choose a rear-projection system in which the projector shines on the screen from behind. The projector is typically placed in an adjoining room, closet or crawl space, behind a translucent, transmissive screen mounted in a hole in the wall between the rooms. Sometimes the projector beams its light through a glass wall before hitting the screen surface. An advantage of a rear-projection system is that you may not have to control the room light as tightly as with a front-projection system. A disadvantage is that a rear-projection system is usually more expensive than front projection. And don’t even think about placing speakers behind the screen.

What types of screen accessories are available?

The accoutrements of a well-dressed screen can help protect the projection surface, make the screen more aesthetically-appealing in its integration with the room, absorb sound and light or, in the case of a portable screen, make it easier to transport. Accessories mostly fall into two categories: hardware and woven-ware.

Mounting hardware (brackets and screws) will be included for most any screen meant for installation on a wall or ceiling. The motor and a remote control will almost always be included, too, for a screen capable of lowering itself.  More complex setups may require additional mounting hardware. In the case of a screen used in training or educational settings, you may want to opt for a laser pointer.

The softer side of screen accessories encompasses drapery, skirts and wings. Drapes or curtains can be used to hide a screen fixed to a wall when the projector is idle. Winged drapes flank the screen to focus the audience’s attention during a presentation. A skirt is mounted below the screen. A zippered carrying case can be used to transport a portable screen.

What about a paint-on screen?

If you have a wall in front of your projector that is characterized by a uniformly smooth surface, you can buy special paint in one of several shades. Gray will provide better contrast than white, but white reflects the brightest picture. Don’t forget the paint tray and roller. See “Who Knew B&H Sells Screen Goo?”

The Takeaway

  • A retractable screen (motorized, manual or portable) makes the most sense for a multi-purpose room since the screen can be hidden when it isn’t being used.
  • Movie lovers will want a screen with an aspect ratio of at least 16:9, maybe wider.
  • Projection screens are as often identified by width as by diagonal, so make sure you’re on the same page as the manufacturer.
  • A matte white screen is the most widely used screen type, but a slightly gray screen may help achieve greater contrast in certain circumstances.
  • A perforated screen enables one or more speakers to be placed behind the screen.
  • A high-gain screen helps compete with ambient light or compensate for mediocre projector brightness.

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