Comparison Acer H6541BDK vs BenQ MX550

Main purpose of the projector.

This parameter is somewhat subjective and largely depends on how the device is positioned by the manufacturer; nevertheless, for the most comfortable use, it is best to follow the stated purpose. The options may include: universal, for presentations, for home theater, professional, portable, gaming. Here is a more detailed description of each option:

— Universal. The simplest type of projector, roughly speaking—any model that does not belong to one of the specializations described below. Most have fixed optics, a projection distance of 1 – 12 m, an image diagonal of approximately 1 – 7 m (see below), and a relatively low price.

— For presentations. Projectors primarily intended for business use, particularly for giving presentations. They generally have a short projection distance with a fairly large image diagonal, allowing them to be used in small rooms; they can work with both widescreen and standard image formats (see below), and support resolutions typical of computer graphics cards—for example, 1280х800. At the same time, the native resolution itself (see below) may be quite low. In addition, an almost mandatory feature of this type of projector—with rare exceptions—is a 15-pin D-Sub...input (see “Connectors”).

— For home theater. Projectors intended primarily for watching films. The main criterion for assigning a particular model to this category is how the projector is positioned by the manufacturer itself (in other words, whether this purpose is specified in the official documentation). However, there are also some common features: cinema-oriented models generally support widescreen image formats, have a high native resolution (see below), allowing them to work with HD video, and are equipped with the appropriate interfaces (see “Connectors”).

— Professional. High-end projectors with advanced specifications, numerous features and, accordingly, a considerable price. They are characterized by high image contrast ratios, support high-resolution video (including cinematic image formats), feature optical zoom for scaling the image without loss of quality, allow the connection of multichannel audio systems, and much more. The specific set of options in professional projectors may vary depending on the model, but in any case, these are fully loaded devices with top-tier specifications.

— Portable projector. An ultra-compact type of projector: most models are small enough to be carried in a pocket. These devices are primarily intended for giving impromptu presentations. Their form factor and power supply can vary. Some models are standalone devices with their own built-in storage and batteries (and sometimes even a full-fledged mobile OS such as Android on board). Others are designed like external cases or add-ons and, when in use, are attached directly to a mobile phone, using it as the signal and power source. However, in all cases, portable projectors have rather modest specifications due to their small size—for example, they have neither high brightness nor high image contrast. Battery life (in models with their own batteries) generally ranges from 40 minutes to an hour and a half. Energy-efficient LED lamps are also characteristic of this type (see below).

— Gaming. Specialized projectors intended for use with video games. Externally, they often feature a distinctive “aggressive” design, which may follow the style of a particular line of gaming PCs or laptops. As the name suggests, their practical specifications are primarily geared toward delivering a high-quality gaming image. To this end, projectors for this purpose typically offer, among other things, high native resolution (at least 1920х720, and more often 1920х1080 or higher), color reproduction of 1 billion colors, support for refresh rates (see below) of up to 120 Hz inclusive, and at least one HDMI input for receiving a digital signal from a computer graphics card. In addition, such models often support 3D. The maximum image diagonal may reach 7.5 m or more; this category also includes ultra-wide-angle devices capable of providing an image diagonal of about 3 m from a distance of about half a meter.

— HD (High-intensity discharge). General name for gas discharge lamps, i.e. lamps in which the light flow is created by an electrical discharge between the electrodes inside the bulb. In the case of projectors, such lamps can be mercury, metal-halide, and xenon (see above for more details).

— LED. LEDs are used as a light source. They provide high brightness with low power consumption.

— Laser-LED. Light source based on laser LEDs. It has even greater brightness than classic LED, with relatively low power consumption.

— UHP (Ultra-high performance) — a high-pressure mercury lamp, developed by Philips. Compared to other lamps, it consumes less power, while not inferior in brightness. Projectors on such lamps are smaller and lighter than conventional ones due to a smaller power supply, the cooler operates with a lower noise level. The creators claimed a service life of up to 10,000 hours. One of the most popular types of lamps for projectors today

– UHE (Ultra-High Energy). Variety of UHP lamps (see above).

— UHB (Ultra-high brightness). Another kind of UHP lamps (see above).

— NSH (New Super High Pressure). Also applies to high pressure mercury lamps manufactured by Ushio. Somewhat less popular than UHP and its peers, but also widespread. Estimated operating time is about...2000 hours.

— SHP. High pressure mercury lamps manufactured by Phoenix.

— P-VIP (Video Projector) — a high-pressure mercury lamp from OSRAM. High brightness lamps, service life — 4000 — 6000 hours.

—UHM (Ultra High Performance Lamp of Matsushita) is a high pressure mercury lamp manufactured by Panasonic. Сan be easily changed, operating time, depending on type — 2000 — 5000 hours.

— Xenon. The design and principle of operation of such lamps are similar to high-pressure mercury lamps — light is created due to a discharge in a gaseous medium. However, instead of mercury vapor, in this case, an inert xenon gas under high pressure is used. This allows to create high power lamps (from 2 kW) with the appropriate light flow. Xenon lamps are used primarily in professional models.

— HPM. High-pressure mercury lamp technology developed by Sony and used primarily in its projectors (although other brands are also available). Combines compact size and relatively low cost with high brightness.

— DC. Abbreviation for "direct current". In the case of projector lamps, this designation usually refers to mercury lamps powered by direct current. The operating voltage of such lamps in different models of projectors may be different. Their design usually uses various tricks to improve performance compared to conventional lamps of this type — in particular, increase service life and reduce power consumption without sacrificing brightness.

— AC. This abbreviation stands for "alternating current". Such lamps are similar in almost everything to the DC ones described above, differing from them only in the type of power supply.

The lamp model that the projector is designed for. Most projectors come with lamps included, so this information is not needed for normal use. But when looking for a spare lamp or replacement, information about model can be very useful: finding a spare part by the exact name is much easier than by general data like the brand of the projector.

When working in economy mode, the brightness of the backlight is noticeably reduced, on average by 30-50%. With a decrease in brightness, heat dissipation also decreases, which saves the working life of the illuminator, thereby increasing the lamp life. Thus, the ECO mode allows you to extend the lamp life by an average of 30%. If the typical projector lamp life is 4000 hours, regular use of the ECO mode will extend the backlight life to approximately 5500 hours.

The power consumption of the backlight lamp installed in the projector.

Theoretically, the more powerful the lamp, the brighter it is. However, this is only true when comparing lamps of the same type (see above); and even in this case, the brightness may also depend on the nuances of the design. Therefore, when evaluating the capabilities of a lamp, it is worth focus not so much on power, but on the directly claimed brightness in lumens (see below).

But what this parameter directly affects is the total power consumption of the projector: the lamp is the most “greedy” component of the device, compared to it, the power consumption of the rest of the electronics is very small. Also note that many powerful lamps have high heat dissipation and require cooling systems, which affects the size and weight of the projector.

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 dynamic image contrast provided by the projector.

Dynamic contrast ratio is the ratio between the brightest white and darkest black colour that a projector can produce. Recall that the quality of colour reproduction and detailing depend on contrast, the higher this indicator, the lower the likelihood that details will be indistinguishable in bright or dark areas. However, dynamic contrast is a rather specific parameter. The fact is that when it is calculated, the brightest white at the maximum brightness settings and the darkest black at the minimum are taken into account. As a result, the figures in this column can be very impressive, but it is impossible to achieve such a contrast within one frame.

By introducing this parameter, the manufacturers went to a certain trick. However, this is not to say that dynamic contrast has nothing to do with image quality at all. Projectors can use automatic brightness control, in which the overall brightness, depending on the "picture" on the screen, can increase or decrease. This format of work is based on the fact that the human eye does not need too bright areas on a general dark background and very dark areas on a bright one, the image is normally perceived even without it. The maximum brightness difference achievable in this mode of operation is exactly what described by dynamic contrast.

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.

Horizontal frequency supported by the projector.

This parameter is relevant when working with analogue video signal. In such a video, the image is formed line by line: each pixel in the line is highlighted in turn, then the next line is highlighted, and so on. The horizontal frequency describes how many times per second the backlight beam runs from edge to edge of the screen. For normal playback, the projector must support the same refresh rate as the input signal was recorded. However, most models support a fairly wide range of frequencies, and there are no problems with support. Also note that if you are not a professional, then when choosing a projector, it is quite possible to focus on the frame rate (see below) — this parameter is simpler and more intuitive, and support for a certain frame rate automatically means support for the corresponding line rate.