The matching screen in the home cinema

A beamer is only slightly more than half the rent. The canvas also has a great influence on the image.


Wall or canvas


Does it have to be a purchased canvas? Or is a white wall enough? The answer of the professional is: low-priced screens are hardly better than a matt-white smooth wall. Structures such as a razor wallpaper or flaws in the plaster disturb the film enjoyment however considerably. In this case, the handyman can grab a wooden plate and paint it white.


The color


The pigmentation makes the difference between a good and a bad canvas. Good coatings improve the contrast, the colors and thus the overall image impression. For the home cinema and the projection with Full HD is worth a canvas with good quality.


Matt or glossy


This question affects the so-called gain factor (see below). A matt, evenly reflective surface is ideal for home cinema. This allows a wide viewing angle. Only for special applications a glossy or reflective coating is recommended. Their stronger reflection leads to glaring spots - the so-called hotspots - at certain viewing angles.


The border


Practice: The right projector in the home cinema


Screens with diffuse reflection are also called Type D. Reflective canvases are of type S. They reflect the light particularly strongly in the middle of the room and are therefore more suitable for bright, not darkened rooms. Another special case is type B: he throws the light of a table projector back towards the spectators - also unsuitable for the home cinema.


A black masking around the screen greatly improves the contrast. In addition, a dark hue is an advantage for the wall around the screen.


The bigger, the better - this is not true. The ratio of viewing distance to image size must be correct. The image resolution specifies the minimum distance. Otherwise, the individual pixels interfere if you sit too close to the screen. The higher the resolution, the closer to the image.


For Full HD, a minimum viewing distance of approximately 1.7 x image width is estimated. So if you sit four meters in front of the screen, the image width should be a maximum of 2.40 meters. The height of the screen results from the aspect ratio. At 16: 9, a height of 1.34 meters from a width of 2.4 meters.


Many blockbusters are rotated in CinemaScope format 21: 9. Film fans therefore often prefer screens with this narrow aspect ratio. Of course, a 21: 9 picture can also be projected onto a 16: 9 screen. But then light gray stripes interfere above and below. Ideal are so-called multiformat screens with an adjustable black masking. Multiformat screens are usually powered by motor - with an additional motor for masking.


The two classics are frame and roller blinds. There are also other variants, especially for transport. Examples are the stand, folding or suitcase screens. The luxury version for the home cinema is motorized.


Frame canvas


It is the classic of home cinema. The cloth is tightly stretched on a frame and remains smooth. This canvas is difficult to stow away and is therefore suitable for fixed mounting. The frame is a view in the room. This is ideal for a home cinema in the basement, in a living room the screen can permanently disturb.


Image size and distance


Roller blind panel


This canvas can be rolled up. The box with the roller can be mounted on a ceiling as well as on a wall. Behind the screen can hang a picture or a shelf. A mechanical roller blind cover can be pulled up by hand. The cloth should be heavy so it does not throw any waves.


The page ratio


Motorcycle


Electric roll-out walls provide great comfort. Soft electric motors roll out the screen or drive it silently. They can be controlled via surface-mounted switches or remote controls. Radio remote controls are used, more infrequently also infrared controls. The receivers must, of course, be installed in the model.


Electric roller screens can be attached to the wall or ceiling like their manual counterparts. In the case of so-called multiformat screens, the upper black masking can be driven precisely to the boundary of the projected image. However, two engines are necessarily required, and the price is therefore higher.


Canvas types


The material


Acoustic walls


What is the gain factor?


Practice: Home cinema - planning and room selection


The control of the motor can in principle also be connected to a home automation or media control. Thus, for example, one can start the beamer with one button, dimm the light and extend the screen. There are several manufacturers that offer such solutions. Crestron is used, for example, in the professional field; the instabus EIB system is used in the home.


Alphaluxx produces high-quality screens with and without a motor, one of the few companies to manufacture in the United States according to customer requirements. There are high-quality screens from Screen Research or Stewart.


Cheap screens are made of PVC plastic. PVC has the advantage that it is smooth at the time of purchase. But a few months later wrinkles are formed - the beautiful picture is gone. On the other hand, it is different in tissue: it has to hang out for a while.


Practice: Speakers and AV receivers in the home cinema


But then it will be in shape for more than ten years. Modern canvas fabrics consist of carbon and glass fibers. Large cinema walls are interwoven with steel fibers. Natural fibers are mainly used for health reasons. The back of the fabric should be black. This prevents the background from passing through.


In the cinema, the center speaker is placed behind the screen. The voices of the actors always come from the middle. But thick cloth dampens especially higher frequencies. The result is a dull sound. Acoustic walls improve the treble reproduction. Many small holes in the cloth make the canvas sound-permeable. But these screens also reflect a little less light. Moiree patterns are also reported to be disturbing.


The luminance or gain factor is a measure of the reflective properties of a screen. A screen, which reflects the incident light uniformly in all directions, has a gain factor of 1. The viewers sitting in the middle, therefore, see an equally bright picture as the viewer at the edge. Screens with a higher gain factor bundle the light perpendicular to the screen. Viewers in the middle see a brighter picture than the film fans sitting sideways.