Comparison Kivi 24FR55WU 24 " vs Liberton 22AS4FHDTA1 22 "

The optimal size of the TV depends primarily on the distance from which it is planned to watch. If the diagonal on the screen is too small, it will be difficult to see the details, you will have to strain; if too large, the image will be much larger than the field of view, which is also undesirable. The best option is the situation when the distance to the TV corresponds to 3 - 4 of its diagonals: for example, for a size of 32 "(80 cm), the recommended distance is about 2.5 - 3 m.

The size of the diagonal of the screen affects both the cost of the TV and its general equipment. So, among models smaller than 32" there are often TVs without Smart TV and other advanced features; TVs for 32 - 55" can be both quite simple and advanced; and a large screen, more than 55", in most cases is combined with extensive additional functionality.

Now the following popular diagonals are on the market: 32 ", 39 - 40", 43", 49", 49 - 50", 55", 65", 75" and more than 80".

The type of coating used on the TV screen.

— Matte. Historically, the first type of coating for LCD screens, which is often found today. Screens with such a coating generally have average characteristics of brightness, saturation and colour reproduction quality, in terms of these indicators they are inferior to glossy counterparts. However, the matte coating has one important advantage: it has virtually no glare from ambient light. In some situations, this can be an important advantage — for example, if the TV is installed opposite the window. And for some users it is more pleasant to look at the screen without glare, albeit relatively dim.

— Glossy. A coating designed to improve the brightness and colour quality of the visible image compared to matte screens. The creators have managed to achieve this goal: "glossy" screens really provide rich, vibrant colours and a brighter image. The key disadvantage of such screens is the appearance of glare from ambient light on them — this can ruin the whole viewing experience. Because of this, the classic glossy coating is practically not used today, anti-glare solutions have taken its place (see below).

— Glossy (anti-glare). Modification of the glossy coating, created, as the name implies, in order to eliminate the main drawback of the classic gloss — glare from external lighting. This is not to say th...at such screens do not glare at all, but there are much less reflections on them than on ordinary glossy ones. As for the image quality, it is at least not much worse, and often even better (especially since such coatings are constantly being improved). Thanks to all this, most modern TVs of all price categories are equipped with anti-glare screens.

The level of dynamic contrast provided by the TV screen.

Contrast in a general sense is the ratio in brightness between the brightest whites and the darkest blacks that the screen can produce. Other things being equal, the higher the screen contrast, the better the quality of colour reproduction and detail, the lower the likelihood that it will be impossible to see details in too bright or too dark areas of the image. Formally, the main characteristic of screens is static contrast (see above), but even in advanced matrices it is relatively low. Therefore, manufacturers went to the trick, introducing such a characteristic as "dynamic contrast".

Dynamic contrast ratio is the difference between the brightest whites at the highest screen brightness settings and the darkest blacks at the lowest. These contrast ratios can be quite impressive—much higher than static—however, it is impossible to achieve such values within a single frame, and dynamic contrast ratio is stated more for promotional purposes than for describing the actual specifications of the screen. However, it cannot be said that this indicator is completely unrelated to reality. The fact is that many TVs use automatic brightness control, which changes the settings depending on the characteristics of the image. This control is based on the fact that when displaying bright scenes, there is no need to provide a deep black level, and in dark scenes, high brightness of light areas is not needed — th...ese are the features of the human eye. This means that in bright scenes you can increase the overall brightness, and in dark scenes you can reduce it; the maximum brightness difference achievable in this mode of operation is precisely described by dynamic contrast.

The response time can be described as the maximum time required for each pixel of the screen to change brightness, in other words, the longest time from the receipt of a control signal to the pixel until it switches to the specified mode. The actual switching time may be less — if the brightness changes slightly, it can be calculated in microseconds. However, it is the longest time that matters — it describes the guaranteed response speed of each pixel.

First of all, the frame rate is directly related to the response time (see the relevant paragraph): the lower the response time, the higher the frame rate can be provided on this sensor. However, the actual frame rate may be less than the theoretical maximum, it all depends on the TV. Also note that the overall image quality in dynamic scenes depends primarily on the frame rate. Therefore, we can say that the response time is an auxiliary parameter: the average user rarely needs this data, and in the specifications they are given mainly for advertising purposes.

Dynamic Scene Index (DSI) provided by the TV screen.

DSI is a rather specific parameter that can be called "visible framerate". Its appearance is due to the fact that a high frame rate is highly desirable for dynamic scenes — it provides smooth images and good detail of moving objects. However, for technical reasons, it is not possible to achieve indicators above 200 Hz in most screens. In order to remedy the situation, manufacturers use special technologies that create the effect of increasing the frame rate.

Such technologies may have different names, but they have the same principle of operation — inserting additional frames between the "own" frames of the video being played. And the dynamic scene index describes the overall effectiveness of such technology used in a TV. For example, a DSI of 200 Hz means that the image quality on the screen approximates a frame rate of 200 Hz, although the actual frame rate is often as low as 50-60 Hz.

In the most advanced models, the dynamic scene index can be up to 3000 Hz, and options above 3000 Hz are considered to be TVs with a high dynamic scene index. However, it is worth noting that such specifications are more of an advertising ploy than a real advantage: in fact, the threshold for human perception is 400 – 500 Hz, a further increase in the DSI does not give a clearly visible improvement in the image.

TV support for high dynamic range technology — HDR.

This technology is designed to expand the range of brightness reproduced by the TV; Simply put, an HDR model will display brighter whites and darker blacks than a regular TV. In fact, this means a significant improvement in colour quality. On the one hand, HDR provides a very "live" image, close to what the human eye sees, with an abundance of shades and tones that a normal screen cannot convey; on the other hand, this technology allows to achieve very bright and rich colours.

However for the full use of this feature, you need not only an HDR TV, but also content (movies, TV broadcasts, etc.) that was originally created for HDR. Also note that there are several different HDR technologies that are not compatible with each other. Therefore, when buying a TV with this feature, it is highly advisable to clarify which version of HDR it supports (HDR10, HDR10 + or Dolby Vision). And the following are found:

— HDR10. Historically the first of the consumer HDR formats, less advanced than the options described below but extremely widespread. In particular, HDR10 is supported by almost all streaming services that provide HDR content, and it is also common for Blu-ray discs. Allows to work with a colour depth of 10 bits (hence the name). At the same time, devices of this format are also compatible wi...th content in HDR10+, although its quality will be limited by the capabilities of the original HDR10.

— HDR10+. An improved version of HDR10. With the same colour depth (10 bits), it uses the so-called dynamic metadata, which allows transmitting information about the colour depth not only for groups of several frames, but also for individual frames. This results in an additional improvement in colour reproduction.

– Dolby Vision. An advanced standard used particularly in professional cinematography. Allows to achieve a colour depth of 12 bits, uses the dynamic metadata described above, and also makes it possible to transmit two image options at once in one video stream — HDR and standard (SDR). At the same time, Dolby Vision is based on the same technology as HDR10, so in modern video technology this format is usually combined with HDR10 or HDR10+.

The TV's connectivity is based not only on wireless technologies (described above), but also on a wired connection. In particular, video transmission can be carried out through VGA, Component, Composite, SCART connectors. Some of them also provide sound transmission, in addition to which there may be a mini-Jack (3.5 mm). and other ports for interconnection with external devices. More about them:

— USB. Connector for connecting external peripheral devices. The presence of USB means at least that the TV is capable of playing content from flash drives and other external USB media. In addition, there may be other ways to use this input: recording TV programs to external media, connecting a WEB camera (see same paragraph), keyboard and mouse to use the built-in browser and other software, etc. The specific set of options depends on the functionality of the TV, it should be specified separately in each case.

— Card reader. A device for working with memory cards, most often in SD format. The main use of the card reader is to play content from such cards on a TV; such an opportunity is especially convenient for viewing materials from photo and video cameras — it is in such devices that memory cards are w...idely used. There may be other ways to use this function — for example, recording from the broadcast or even exchanging files between the card and the TV's storage. It is worth bearing in mind that SD cards have several subtypes — original SD, SD HC and SD XC, and not all of them may be supported by the card reader.

— LAN. Standard connector for wired connection to computer networks (both local and the Internet). Mostly found in models with Smart TV support (including Android TV devices; see related paragraphs). A wired connection is less convenient than Wi-Fi, not as aesthetically pleasing, so manufacturers place more emphasis on a wireless connection, as a result of which the speed indicators of the LAN connector are not indicated, and in some cases may be unacceptable for 4K broadcasts.

— VGA. Analogue video input, also known as D-sub 15 pin. Initially, the VGA interface was developed for computers, but due to the emergence of more advanced standards like HDMI (see below) and technical limitations (the maximum resolution is only 1280x1024, the inability to transmit sound), it is considered obsolete and is used less and less. So it makes sense to specifically look for a TV with such a connector mainly in cases where it is planned to be used as a monitor for an outdated computer or laptop.

— Component. Video interface with 3 connectors, each of which is responsible for its part of the video signal. This separation provides high bandwidth and noise reduction, making the component input the most advanced analogue video interface available today. So, it is capable of working with HD, and in terms of image quality it significantly surpasses S-Video and composite connector, closely approaching HDMI (see below).

— Composite. Combined analogue audio/video interface, it is this connector that is usually called the A/V input. Actually, there are usually three connectors in the composite interface — separately for video and the left/right channel of stereo sound (on TVs with one speaker that do not support stereo, one of the audio connectors is missing). The image quality when working through such an input is not high, and HD formats are not supported at all; on the other hand, the composite interface is extremely widespread not only in modern, but also in outdated equipment like VHS video recorders.

— SCART. The large universal multimedia connector, the largest connector used in today's consumer-grade video equipment. Works mainly with an analogue signal, which is why it is considered obsolete; however, still not falling into disuse. One of the reasons for this "longevity" is versatility: SCART does not have its "own" signal format, this standard only describes the connector. In fact, having the appropriate cables, you can connect different types of incoming signals to such an input — composite, S-Video, etc. Moreover, it is technically possible for such a connector to work as an output (for the same signal types). However the specifications of SCART connectors in different TVs may be different, so a specific list of compatible interfaces needs to be specified separately.

— COM port (RS-232). A connector originally developed for computer technology. It is used as a control on TVs: by connecting the device to a computer, you can control TV parameters and various settings, sometimes quite specific and inaccessible when using a conventional remote control.

— Mini-Jack (3.5 mm). A connector most commonly used as an analogue audio (line) input. One of the options for using such a connector is to connect audio for a video signal transmitted via VGA, S-Video (see above) or another interface that does not support audio transmission. However, with the appropriate cable, any audio source can be connected to the 3.5 mm mini-Jack port, including a mobile device like a smartphone or a pocket player. In this case, the sound can be played both through the speakers of the TV, and on external speakers connected to it. Another option for using this input is to connect a microphone for chatting via Skype.

The number of HDMI inputs provided in the design of the TV.

HDMI is a comprehensive digital interface that allows high-definition video and multi-channel audio to be transmitted over a single cable. It is widely used in modern HD equipment — in fact, the presence of such an output is mandatory for modern media centers, DVD players, etc. Therefore, LCD TVs in the vast majority of cases are equipped with at least one HDMI port. And the presence of several such ports allows you to simultaneously connect several signal sources and switch between them; in some models, the number of HDMI can reach 4 or even more. At the same time, some manufacturers use technologies that allow you to control devices connected to the TV via HDMI from a single remote control.

— Coaxial (S/P-DIF). An interface for transmitting audio in digital format, which allows to transmit multi-channel audio via a single cable with an RCA connector (“tulip”). In terms of resistance to interference, this standard is somewhat inferior to the optical one (see below) — this is due to the fundamental differences between these interfaces. On the other hand, electrical cable is more reliable than optical fibre and is not as sensitive to pressure and bending.

— Optical. An output for transmission of a digital audio signal on a fibre optic cable; allows the transmission of multi-channel audio. Notable for its complete insensitivity to electromagnetic interference. On the other hand, fibre optic cable is quite fragile, it must be protected from bending and strong pressure.

— Mini-Jack (3.5 mm) for headphones. Standard 3.5mm headphone jack. Headphones can come in handy if you need to keep quiet and you can’t use the TV speakers – for example, at a later time of the day; or vice versa, if the environment is noisy and the sound of the TV is hard to hear. Most modern "ears" use a mini-Jack plug, so this connector is the standard headphone output in TVs. And in some models, this output can also be used as a linear output — for example, to connect individual speakers, a sound recording device, etc.

— Subwoofer. A separate output for connectin...g a subwoofer to a TV is a speaker for reproducing low and ultra-low frequencies. Audio systems without subwoofers usually reproduce these frequencies quite poorly. The use of subwoofer allows you to achieve the most deep and rich sound, which is especially important when watching movies with a lot of special effects or high-quality recordings from concerts. At the same time, it is worth noting that such outputs are quite rare in TVs: it is assumed that a full-format external audio system is more suitable for a demanding listener than a separate subwoofer.

— Line. Standard analogue audio interface; usually, provides the transmission of two-channel stereo. It is used primarily to connect active speakers and other audio equipment (for example, audio receivers or power amplifiers) to TVs. It can use different types of connectors, but most often it provides either a 3.5 mm mini-Jack or a pair of RCA jacks for tulip cables. Note that it is a separate line output that is meant here; in some models, this function can be performed by a 3.5 mm headphone jack (see above), but for them the presence of a line-out is not indicated.