Before choosing a projection screen, you need to pay attention to several important factors that will define the final result, namely: roll-out drive, screen proportions, screen size, surface type, framing and the presence of tensioners. You will also find information on what mistakes not to make so that the screen you choose and install is perfectly suited to your needs.
Projection screens can be divided into manual extension and electric.
The former have a catch with which the screen is unrolled manually. Fixing the position is done with a ratchet that locks the screen in the final position. The construction is simple, and the sheer size of the cassette of such a screen is smaller, given the less complicated unrolling mechanism. This solution is ideal for those who are looking for a basic screen based on a simplified design and with a low price.
Electrically rolled-out screens can be activated with an infrared remote control or with a so-called "trigger". The very type of this mechanism allows you to set the level of screen extension more precisely (which is especially important if it is a screen that supports different aspect ratios), and its operation is much more comfortable for the user than in the case of manual extension. The cassettes are slightly larger, which makes the most common type of installation is the installation in the ceiling. Trigger in projection screens is a solution that allows you to synchronize the unrolling mechanism with the projector start-up, so that the whole thing happens simultaneously. The most common form is a wall-mounted switch.
The aspect ratio or format, is one of the most important features to consider when choosing a projection screen.
There is a reason why a large number of manufacturers offer exactly the same model of screen, but with different proportions of the active display area. The aspect ratio, or ratio of sides, determines for us how the image from the projector will look like. From the point of view of home use, such as cinema, the best solution will be to use widescreen aspect ratio (16:9 for HDTV and 16:10 for PC) or super widescreen (21:9 Cinemascope), which will allow free playback of movies in their original form. Of course, you also need to take into account what aspect ratios the projector is capable of displaying in accordance with the principle that you match the screen to the projector, not the other way around.
But what about the common 1:1 or 4:3 aspect ratios? These are used much more often for screens that are intended to display images for business presentations, lectures, school classes - then it is much easier to select a screen if its width is the biggest limitation. In addition, it is worth mentioning that the cheapest projectors that can be found in public places have resolutions of, for example, SVGA (800x600 pixels), which is why screens with these aspect ratios work best for the above-mentioned applications.
There are also frame and electrically controlled screens on the market, which have the ability to expand not only vertically, but also horizontally, so you can change the proportions of the active surface and thus adjust the projected image depending on the projector used.
Once the aspect ratio has been determined and selected, you can move on to selecting the exact dimensions of the projection screen.
The choice of the width of the screen (and thus its height at a fixed aspect ratio) depends on a number of factors:
So how to choose the correct dimensions of a projection screen? The proportion according to which the width of the screen should be between 50% and 67% of the viewer's distance from the screen is considered to be the formula, so for example, for a distance of 3 meters, the width of the screen should vary between 150 and 201cm, so that people can comfortably watch the image without moving their eyes to different areas of the screen.
In addition to the active surface itself, it is also worth considering the framing area. When rolled out, the projection screen should end at a height of about 1 meter from the ground assuming the end of the active surface, or in the case of larger rooms - 1/6 of the distance between the screen and the last row (for example, for a room 15 meters long, the screen should end at a height of 2.5 meters).
The black border on the sides not only allows you to more accurately calibrate the projected image from the projector, but also optically increases the contrast, making the image appear much more vivid compared to a white border. Manufacturers also offer runway strips, which can often be extended further. Such a belt allows you to adjust the screen in terms of its overhang, and in the case of a ceiling installation, the height of the room will be the most important criterion. For example, if the height between the ceiling and floor is 3 meters, the height of the active surface will be 120 centimeters, and the height of the cassette is 20 centimeters, the run-up belt should be 60 centimeters long to ensure the best placement in front of the viewer's eyes.
The active surface can come in different versions, and the factors that define the choice are both the type of room and its illumination, as well as the projector's mounting angle and the brightness of the projected image.
Projection screens dedicated to home theaters usually have a gray active surface and a reflectance below gain 1.0. This provides better contrast, black depth and wider viewing angles. Wider viewing angles will provide good image quality even for people who are not directly on axis, making watching movies together more comfortable. In addition, it is a good choice for those with a high brightness projector and rooms with daylight and bright interior design.
However, if the room is dark, the projector has a lower brightness of the projected image, or you want a narrower viewing angle with higher reflectivity, it is worth choosing a screen with a white active surface.
For electrically extendable screens, tensioners can be used. They are responsible for the correct tension when the screen is rolled out and used, so that the projector light is evenly projected onto the active surface without wrinkling the material. Of course, the larger the screen, the greater the inertia of the material and it is more prone to wrinkling. With larger diagonals, the use of tensioners is therefore most justified. However, it is also worth considering this option for a smaller active surface, as this will ensure better image quality and guarantee that the surface will always be perfectly straight and smooth.
First of all, you need to match the projection screen to the projector you already have. Having a weaker lamp, we choose a surface with a higher reflectance, because it is much easier to change the setting of the projector's optics and adjust it to a minimum extent (e.g. optical zoom), than to make adjustments with a screen. The latter is almost impossible due to the fact that screens are custom-made for a specific application and must meet a number of guidelines.
In addition, the class of the projector itself should be matched to the screen. It is worth choosing a projector and screen of the same class, instead of investing in an expensive projector and using a cheap screen for it, which does not allow you to use the full potential of the projector and negatively affects the quality of the projected image.
Another thing to keep in mind is that the screens are made of PVC. To maintain a long life, the screen must not be exposed to temperature changes. So, when planning to install a projection screen, place it away from radiators and fireplaces, do not install it near sunny windows or use it as a blind. This will exclude the manufacturer's warranty, and cause discoloration, deformation and corrugation of the screen.
