Main function
The main function of the projector.
This parameter is rather conditional, it largely depends on how the device is positioned by the manufacturer; however, for the most comfortable use, it is best to follow exactly the stated purpose. The options here can be:
multipurpose,
for presentations,
for home theater,
professional,
portable,
gaming. Here is a more detailed description of each option:
— Multipurpose. The simplest kind of projectors, roughly speaking – all models that do not belong to any of the specializations described below. Most of them have non-interchangeable optics, a throw distance of 1-12 m, an image diagonal of about 1-7 m (see below), and a relatively low cost.
— For presentations. Projectors designed primarily for business use, such as presentations. Usually they have a small throw distance with a rather large diagonal, which allows them to be used in small rooms; capable of working with both widescreen and conventional image formats (see below), and also support resolutions typical for computer graphics cards — for example, 1280x800. In this case, the actual resolution itself (see below) can be quite low. In addition, an almost mandatory feature of this type of projectors (with a few exceptions) is the presence of a
D-Sub 15 pin input (see "Connectors").
— For home theater. Projectors designed primarily for film viewing. The main criterion for classifying a particular model in this category is how the projector is positioned by the manufacturer itself (in other words, whether this purpose is indicated in the official documentation). However, there are some common features: cinematographic models usually support widescreen image formats, have a high real resolution (see below) that allows you to work with HD video, and are also equipped with the appropriate interfaces (see "Connectors").
— Professional. High-quality projectors with advanced parameters, an abundance of functions and, accordingly, a considerable price. They are characterized by high image contrast, support high-resolution video (including cinematic image formats), have optical zoom to scale the image without losing quality, provide the connection of multi-channel sound systems, and much more. The specific set of options in professional projectors may vary depending on the model, but in any case, these are the most charged devices with top-end characteristics.
— Portable projector. An ultra-compact variety of projectors: most models are pocket-sized. Such devices are intended primarily for improvised presentations. The format of work and power supply may be different. So, some models are made as separate devices with their own built-in storages and batteries (and sometimes even with a full-fledged mobile OS like Android on board). Others are similar in design to external cases or consoles and are put directly on the mobile phone during operation, using it as a source of signal and power. However, anyway, portable projectors, due to their small size, have rather low technical specifications — they have neither brightness nor high image contrast.. Battery life (in models with their own batteries) usually ranges from 40 minutes to one and a half hours. Also, this variety is characterized by cost-effective LED lamps (see below).
— Gaming. Specialized projectors designed for use in video games. Outwardly, they are often distinguished by a characteristic “aggressive” design, while the design can be done in the style of a certain line of gaming PCs or laptops. As for the specifications, they, in accordance with the name, are aimed primarily at providing a high-quality game "picture". To do this, projectors for this purpose provide, in particular, high real resolution (not lower than 1920x720, and more often 1920x1080 or more), colour reproduction at the level of 1 billion colours, support for frame rate (see below) up to 120 Hz, and also at least one HDMI input for receiving a digital signal from a computer graphics card. In addition, such models often provide support for 3D. The maximum image diagonal can reach 7.5 m or more; at the same time, ultra-wide-angle devices are also found in this category, capable of providing an image diagonal of about 3 m from a distance of about half a metre.
Number of lamps
The number of lamps provided in the design of the projector.
Most modern projectors have
one lamp, but there are also multi-lamp models. More lamps increase the light flow and, accordingly, the brightness of the image provided by the projector. In addition, in models with
4 lamps, it may be possible to continue working even if one of the lamps burns out — the brightness of the remaining ones is enough to provide the desired brightness. In
two-lamp versions, most often you have to change a burned-out lamp.
Service life
Minimum projector lamp life as stated by the manufacturer. Specified by the total time of continuous operation. Note that if the projector was operated without violations, then upon reaching this time, the lamp will not necessarily fail — on the contrary, it can work for quite a long time. However, when evaluating durability, it is best to focus on the claimed service life.
Brightness
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.
Brightness ANSI Lumens
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.
Colour rendering
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.
Real resolution
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”.
Rear projection
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.
Throw distance, min
The closest distance to the screen that the projector can be used on. Typically, this is the minimum distance at which the image from the projector remains in focus.
This parameter is especially important if the device is to be placed at a small distance from the screen (for example, in a cramped room). Some modern projectors are able to work normally at a distance of 10 – 20 cm. Also note that the throw distances are determined primarily by the lens, and if the initial range of these distances does not suit you, perhaps the situation can be solved by replacing the optics.