Real resolution
The actual image resolution of the projector.
The minimum for modern projectors is actually
the VGA standard, which assumes a resolution of 800x600 or close to it. The lowest of today's high-definition standards is
HD (720) ; the classic size of such a frame is 1280x720, but there are other options in projectors, 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 content being played also corresponds to it.
Image format support
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.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.
Image size
Diagonal size of the image projected by the projector. Usually, it is indicated as a range — from the smallest, at the minimum throw distance, to the largest, at the maximum. About throw distances, see above; here it is worth saying that the choice of diagonal size depends both on the distance between the screen and the audience, and on the format of the projector. For example, to watch a video, the best option is the situation when the distance from the viewer to the image corresponds to 3-4 diagonals, and a relatively large picture can be useful for working with presentations. More detailed recommendations for different situations can be found in special sources; here we only recall that the image must fit on the screen used with the projector.
Throw ratio
The projector's throw distance is vital in determining what size projection screen to use and how far away it should be from the projector. Most projectors have a variable throw ratio. In the extreme positions, these are wide-angle mode (smallest value) and telephoto lens mode (largest value). Knowing these values, you will be able to determine the range of throw distances within which the projector must be placed in order for the projected image to match the specified dimensions of the projection screen.
According to these values, you need to check or set the optical zoom. We divide the larger value by the smaller value, and we get a figure, for example 1.33-2.16: 1.
If we want to calculate whether this projector is suitable for a certain image size, we do this: 1.33*3 (image width)=the distance at which the projector should hang.
Optical zoom
The magnification range of optical zoom that the projector can provide.
Optical magnification of the image is carried out due to the operation of the lenses in the projector lens. With such an magnification, the size of the entire image changes; this can be useful both for adjusting the “picture” to the screen size, and for detailed viewing of individual details (the main thing is that these details do not crawl out of the screen when enlarged). In general,
optical zoom is considered more advanced than digital one, because it allows user to adjust the diagonal without moving the projector, and maintains the original resolution of the "picture" regardless of the magnification. However lenses with such an possibility ("zoom lenses") are more complicated and more expensive than fixed optics, but the difference in price is almost imperceptible compared to the cost of the projectors themselves.
Operating time
The maximum operating time that the projector can run on battery. It is worth considering that manufacturers in most cases indicate the value at the minimum brightness settings, when using the device in the optimal (and even more so in the maximum) mode, this figure will be less.
Operating time (energy-saving mode)
Maximum operating time of the projector from built-in batteries in economy mode. The indicator primarily depends on the capacity of the built-in battery. Of course, when working in economy mode, the maximum brightness and contrast of the device are significantly reduced. As a general rule, when powering the projector from the built-in battery, the place where the device is being used should be well shaded.
Power consumption
The power consumed by the projector during normal operation. Both the high consumption of the device and the requirements for power supply providing depend on this indicator: for example, heavy professional projectors of 3500 W and above cannot be plugged into standard sockets, they require a special connection format.
Keep in mind that when using traditional mercury or gas discharge lamps, high brightness inevitably requires high power. Energy efficient LED projectors do not have this disadvantage, but they are still relatively uncommon, and LED is not always a suitable type of lamp.
