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The brightness of the image produced by the projector at maximum backlight brightness. Usually, the average brightness of the screen, derived from a special formula, is indicated. The higher it is, the less the image depends on ambient light: a bright projector can provide a clearly visible image even in daylight, but a dim one will require dimming. On the other hand, increasing brightness reduces contrast and accuracy of colour reproduction.

Accordingly, when choosing this parameter, you need to consider the conditions in which you plan to use the projector. So, for office or school/university use, a brightness of at least 3000 lm is desirable — this allows you to get normal visibility without obscuring the room. In turn, among the top models a very low brightness can be found, because. such projectors are usually installed in rooms specially designed for them with good darkness level. And in ultra-compact devices it is impossible to achieve high brightness for technical reasons.

Detailed recommendations on the optimal brightness for certain conditions can be found in special sources. Here we note that anyway, it is worth choosing according to this indicator with some margin. As mentioned above, as brightness increases, contrast and colour quality decrease, and you may need to use the projector at a reduced brightness to achieve the desired picture quality.

This parameter largely determines the ability of the projector to work in a well-lit room. For a dark room, 1000 lumens is enough to make the projection picture bright, rich, clear and understandable. But when working in a lit room, the projector will need at least 3500-4000 lumens. Do not confuse ANSI lumens with Peak lumens. These are two different brightness standards. To convert one type of brightness to another, you need to multiply Peak lumens by 10-12. The result will be an approximate value of ANSI Lumens.

However, experts do not recommend chasing high ANSI lumen brightness values. There are many professional projectors with brightness up to 3500 lm. The lower the brightness, the lower the power consumption, and at the same time, the life of the illuminator increases. Of course, if the projector will be installed in a work office or classroom where good lighting is required, it is recommended to purchase a model with ANSI Lumens brightness of 4000 lumens and more.

The number of individual colour shades that the projector is capable of displaying.

The minimum indicator for modern projection technology is actually 16 million colours (more precisely, 16.7 million is a standard number associated with the features of digital image processing). In the most advanced models, this value can exceed 1 billion. However, two nuances should be taken into account here: firstly, the human eye is able to recognize only about 10 million colour shades, and secondly, not a single modern image output device (projectors, monitors, etc.) cannot cover the entire spectrum of colours visible to the human eye. Therefore, impressive colour performance is more of a marketing ploy than a real indicator of image quality, and in fact it makes sense to pay attention to other characteristics — primarily brightness and contrast (see above), as well as specific data like a colour gamut chart.

The size of the panel/chip affects the depth and final quality of the image. The larger the panel/chip, the more light it is able to process, which means the picture will be clearer and more structured. The average projector has a sensor of 0.5-0.7″, advanced projectors use sensors of 1.2-1.5″ and more.

The native resolution of the image produced by the projector matrix.

The minimum for modern projectors is actually the VGA standard, which assumes a resolution of 800x600 or close to it. The most limited of modern high-definition standards is HD (720); the classic size of such a frame is 1280x720, but projectors also have other options (up to 1920x720). A more advanced HD format is Full HD (1080), which also has several variations (the most popular is 1920x1080). And among high-end projectors there are models of Quad HD, Ultra HD (4K) and even Ultra HD (8K) standards.

In general, the higher the resolution, the clearer and more detailed image the projector can produce. On the other hand, this indicator directly affects the cost, and all the benefits of high resolution can only be appreciated if the reproduced content also corresponds to it. Note that modern projectors can work with higher resolutions than the “native” ones – for more details, see “Maximum video resolution”.

Image formats supported by the projector.

In this case, format means the aspect ratio of the image. The general rule in this case is that the projector must support the same format in which the original content is recorded. Otherwise, the image will either be stretched in height or width, or with black stripes on the sides or top-bottom. Specifically, the formats can be divided into three main categories:

— Traditional, or rectangular. Classic formats in which the height of the picture is not much less than the width. The most popular options are 4:3, widely used in analogue TV, and 5:4, common in computer technology. Traditional formats are well suited for presentations, working with documents and graphics, and other similar tasks.

— Widescreen — formats in which the frame width is significantly (more than 1.5 times) greater than the height. The most popular of these standards are 16:9 and 16:10. These aspect ratios are well suited for games and movies; in particular, most high-definition content (HD 720p and above) is recorded in widescreen format.

— Extra wide. The formats are even wider than the widescreen ones described above — for example, 21:9. Mainly used in cinematography.

It is worth noting that many modern projectors are able to work with several types of formats at once — for example, with classic 4:3 and...wide-angle 16:9.

Support by the projector of one or another technology of brightness/contrast enhancement.

Usually in such case, software image processing is implied to improve brightness and/or contrast (if necessary). Specific processing methods may be different — in particular, in some cases we are actually talking about turning standard content into HDR, and some manufacturers do not specify technical details at all. The effectiveness of different technologies can also be different, and besides, it is highly dependent on the specific content: in some cases, the improvement will be obvious, in others it may be almost imperceptible.

The ability of the projector to operate in the rear projection mode (“mirroring” the image).

There are two main types of rear projection. Most often, horizontal mirroring is found in projectors — it is used when installing the device behind a translucent screen. Vertical inversion, in turn, is used in projectors with fixed keystone correction — due to their design, when mounted under the ceiling, such devices must be turned upside down, which requires the corresponding correction of the displayed image.

The farthest distance from the screen that the projector can be used on. This is the maximum distance at which the image remains in focus and maintains acceptable brightness — at least enough for viewing in a darkened room on a high-quality screen.

It is necessary to choose according to this parameter taking into account the expected operating conditions and the distances to be dealt with. At the same time, it's ok to have a certain margin for the maximum distance — since, as already mentioned, it is usually indicated for an perfect screen and a darkened room, and such conditions are not always available. Also note that although the throw distances depend on the lens, not every projector with an interchangeable lens allows the installation of more "long-range" optics than the standard one — the device may simply not have enough brightness for an increased distance.