The monitor is designed to display information from a computer in a graphical form. The comfort of working at the computer depends on the size and quality of the monitor.
The most optimal in terms of price / quality ratio today are LG 24MP58D-P and 24MK430H.
Monitor LG 24MP58D-P
There are also similar models Samsung S24F350FHI and S24F356FHI. They do not differ in quality from LG, but maybe someone will like the design better.
Monitor Samsung S24F350FHI
But DELL S2318HN and S2318H already significantly surpass the monitors of Korean brands in the quality of electronics, case materials and firmware.
Monitor DELL S2318HN
If you are not satisfied with the DELL design, then pay attention to the HP EliteDisplay E232 and E242 monitors, they are of the same high quality.
HP EliteDisplay E232 Monitor
2. Monitor manufacturers
The best monitors come from Dell, NEC and HP, but they are also the most expensive.
Monitors of large European brands Samsung, LG, Philips, BenQ are especially popular, but in the budget segment there are many models of low quality.
You can also consider monitors of well-known Chinese brands Acer, AOC, Viewsonic, which are of average quality in the entire price range, and the Japanese brand Iiyama, under which both expensive professional and budget monitors are produced.
In any case, read the reviews and reviews carefully, paying particular attention to the drawbacks (poor image quality and build quality).
3. Warranty
Modern monitors are not of high quality and often fail. The warranty for a quality monitor should be 24-36 months. The best in terms of quality and speed, warranty service is offered by Dell, HP, Samsung and LG.
4. Aspect ratio
Previously, monitors had a 4: 3 and 5: 4 width-to-height ratio, which is closer to a square shape.
There are not many such monitors, but they can still be found on sale. They have a small screen size of 17-19 ″ and this format is suitable for office or some specific tasks. But in general, such monitors are no longer relevant, and are generally not suitable for watching films.
Modern monitors are widescreen and have aspect ratios of 16: 9 and 16:10.
The most popular format is 16: 9 (1920 × 1080) and is suitable for most users. The 16:10 aspect ratio makes the screen a bit taller, which is more convenient in some programs with a large number of horizontal panels (for example, when editing video). But at the same time, the screen resolution should also be slightly higher in height (1920 × 1200).
Some monitors have an ultra-wide 21: 9 aspect ratio.
This is a very specific format that can be used in some types of professional activity where it is necessary to work with a large number of windows at the same time, for example, design, video editing or stock quotes. Now this format is also actively promoted in the gaming industry, and some gamers note a greater convenience thanks to the expanded view in games.
5. Screen diagonal
The 19 ″ screen is too small for a widescreen monitor. For an office computer, it is advisable to purchase a monitor with a screen diagonal of 20 ″, since it will not be much more expensive than 19 ″, and it will be more convenient to work with it. For a home multimedia computer, it is better to purchase a monitor with a screen diagonal of 22-23 ″. For a gaming computer, a screen size of 23-27 ″ is recommended, depending on personal preferences and financial capabilities. To work with large 3D models or drawings, it is advisable to purchase a monitor with a screen diagonal of 27 ″.
6. Screen resolution
Screen resolution is the number of dots (pixels) in width and height. The higher the resolution, the clearer the image and more information fits on the screen, but the text and other elements become smaller. In principle, problems with small fonts are easily solved by enabling scaling or enlarging fonts in the operating system. Keep in mind that the higher the resolution, the higher the requirements for the power of the video card in games.
In monitors with a screen up to 20 ″, this parameter can be ignored, since they have the optimal resolution for them.
22 ″ monitors can have a resolution of 1680 × 1050 or 1920 × 1080 (Full HD). Monitors with a resolution of 1680x1050 are cheaper, but videos and games will look worse on them. If you will often watch videos, play games or do photo montage, then it is better to take a monitor with a resolution of 1920 × 1080.
23 ″ monitors generally have a resolution of 1920 × 1080, which is the most optimal.
24 "monitors are generally 1920 x 1080 or 1920 x 1200. 1920 × 1080 is more popular, 1920 × 1200 has more screen height if you need it.
Monitors 25-27 ″ or larger can have a resolution of 1920 × 1080, 2560 × 1440, 2560 × 1600, 3840 × 2160 (4K). Monitors with a resolution of 1920 × 1080 are optimal in terms of price / quality ratio and in terms of gaming performance. Higher resolution monitors will provide better picture quality, but they will cost several times more and require a more powerful graphics card to play games.
Monitors with an ultra-wide screen (21: 9) have a resolution of 2560 × 1080 or 3440 × 1440 and, if used in games, will require a more powerful graphics card.
7. Matrix type
The matrix is called the liquid crystal screen of the monitor. Modern monitors have the following types of matrices.
TN (TN + film) is a cheap matrix with average color quality, clarity and poor viewing angles. Monitors with such a matrix are suitable for ordinary office tasks and are not suitable for watching videos with the whole family, as they have poor viewing angles.
IPS (AH-IPS, e-IPS, P-IPS) - a matrix with high color quality, clarity and good viewing angles. Monitors with such a matrix are perfect for all tasks - watching videos, playing games, designing, but they are more expensive.
VA (MVA, WVA) is a compromise between TN and IPS matrices, has high color rendering quality, clarity and good viewing angles, but does not differ much in price from inexpensive IPS matrices. Monitors with such matrices are no longer very relevant, but they can be in demand in design activities, as they are still cheaper than professional IPS matrices.
PLS (AD-PLS) is a more modern cheaper version of the IPS matrix, which has high color reproduction quality, clarity and good viewing angles. In theory, monitors with such matrices should be cheaper, but they appeared not so long ago and their cost is still higher than analogs with an IPS matrix.
Since monitors with IPS and PLS matrices are no longer much more expensive than those with TN, I recommend purchasing them for home multimedia computers. However, IPS and TN matrices also come in different qualities. Usually those that are simply called IPS or TFT IPS are of lower quality.
AH-IPS and AD-PLS matrices have a lower response time (4-6 ms) and are more suitable for dynamic games, but their overall image quality is lower than that of more expensive modifications.
The e-IPS matrix already has a significantly higher image quality and is better suited for design tasks. Semi-professional monitors are equipped with such matrices, the best of which are produced by NEC, DELL and HP. Such a monitor will also be an excellent choice for a home multimedia computer, but it is more expensive than analogs based on cheaper IPS, AH-IPS and PLS matrices.
The P-IPS matrix is of the highest quality, but it is installed only in the most expensive professional monitors. Also, select e-IPS and P-IPS monitors are color-calibrated at the factory for perfect color out-of-the-box with no professional setup required.
There are also expensive gaming monitors with high-quality TN matrices with low response time (1-2 ms). They are specially "sharpened" for dynamic shooters (Counter-Strike, Battlefield, Overwatch). But due to the poorer color reproduction and poor viewing angles, they are less suitable for watching videos and working with graphics.
8. Screen cover type
Matrices can be matte or glossy.
Frosted screens are more versatile, suitable for all tasks and any external lighting. They look duller but have a more natural color reproduction. Quality matrices usually have a matte finish.
Glossy screens look brighter and tend to have sharper darker colors, but are only suitable for watching videos and playing games in a darkened environment. On a glossy matrix, you will see reflections of light sources (sun, lamps) and your own, which is rather uncomfortable. Usually such a coating has cheap matrices in order to smooth out imperfections in image quality.
9. Response time of the matrix
The response time of the matrix is the time in milliseconds (ms), during which the crystals can rotate and the pixels change their color. The first matrices had a response of 16-32 ms, and when working on these monitors, terrible trails were visible behind the mouse cursor and other moving elements on the screen. Watching movies and playing on such monitors was completely uncomfortable. Modern matrices have a response time of 2-14 ms and there are practically no problems with loops on the screen.
For an office monitor, in principle, this does not really matter, but it is desirable that the response time does not exceed 8 ms. For home multimedia computers, it is considered that the response time should be on the order of 5 ms, and for gaming computers - 2 ms. However, this is not quite true. The fact is that only low quality (TN) matrices can have such a low response time. Monitors with matrices IPS, VA, PLS have a response time of 5-14 ms and they provide significantly higher image quality, including movies and games.
Do not buy monitors with too low response time (2 ms), as they will have low quality matrices. For a home multimedia or gaming computer, a response time of 8ms is sufficient. I do not recommend purchasing models with a higher response time. An exception may be monitors for designers, which have a matrix response time of 14 ms, but they are less suitable for games.
10. Screen refresh rate
Most monitors have a refresh rate of 60 Hz. This is, in principle, sufficient to ensure flicker-free and smooth images for most tasks, including games.
Monitors supporting 3D technology have a frequency of 120 Hz or more, which is required to support this technology.
Gaming monitors can have a refresh rate of 140 Hz or higher. Due to this, the picture is incredibly clear and does not blur in such dynamic games as online shooters. But it also imposes additional demands on the performance of the computer so that it can provide the same high frame rate.
Some gaming monitors support Nvidia's G-Sync frame sync technology that makes frame rates incredibly smooth. But these monitors are much more expensive.
AMD also has its own FreeSync frame sync technology for video cards of its own design and monitors with its support are cheaper.
To support G-Sync or FreeSync, you also need a modern graphics card that supports the corresponding technology. But many gamers question the usefulness of these technologies in games.
11. Screen brightness
The screen brightness determines the maximum possible backlight level for the screen for comfortable operation in bright outdoor conditions. This indicator can be in the range of 200-400 cd / m 2 and if the monitor does not stand in the bright sun, then it will have a fairly low brightness. Of course, if the monitor is large and you are going to watch video on it with the whole family during the day with the curtains open, then the brightness of 200-250 cd / m2 may not be enough.
12. Screen contrast
Contrast is responsible for the clarity of the image, especially fonts and small details. There is static and dynamic contrast.
The static contrast ratio of most modern monitors has a ratio of 1000: 1 and this is quite enough for them. Some monitors with more expensive matrices have static contrast ratios from 2000: 1 to 5000: 1.
Dynamic contrast is determined by different manufacturers according to different criteria and can be calculated in numbers from 10,000: 1 to 100,000,000: 1. These numbers have nothing to do with reality and I recommend not paying attention to them.
13. Viewing angles
It depends on the viewing angles whether you can or several people at the same time view the contents of the screen (for example, a movie) from different sides of the monitor without significant distortion. If the screen has small viewing angles, then deviation from it in any direction will lead to a sharp darkening or brightening of the image, which will make viewing uncomfortable. The screen with large viewing angles looks good from any side, which, for example, allows you to watch videos in a company.
All monitors with high-quality matrices (IPS, VA, PLS) have good viewing angles, with cheap matrices (TN) - poor viewing angles. The values of the viewing angles that are given in the characteristics of the monitor (160-178 °) can be ignored, since they have a very distant relationship to reality and only confuse.
14. Screen backlight
Older monitors used fluorescent lamps (LCD) to illuminate the screen. All modern monitors use light-emitting diode (LED) to illuminate the screen. LED backlighting is better, more economical and durable.
Some modern monitors support Flicker-Free backlight anti-flicker technology, which is designed to reduce eye fatigue and negative effects on vision. But in budget models, due to the low quality of the matrix, this technology does not give a positive effect and many users complain that their eyes still hurt. Therefore, support for this technology is more justified on monitors with the highest quality matrices.
15. Power consumption
Modern monitors consume only 40-50 W when the screen is on, and 1-3 watts when the screen is off. Therefore, when choosing a monitor, you can ignore its power consumption.
The monitor can have the following connectors (click on the picture to enlarge).
1.
Power socket 220 V.
2.
Power connector for monitors with an external power supply or speaker power.
3.
VGA (D-SUB) connector for connecting to a computer with an old video card. This is optional as an adapter can be used for this.
4,8.
Display Port connectors for connecting to a modern graphics card. Supports high resolutions and refresh rates over 60Hz (for gaming and 3D monitors). Not required if DVI is available and the monitor does not support over 60Hz.
5.
Mini Display Port connector Same smaller format connector, optional.
6.
DVI connector for connecting to a computer with a modern video card. Must be mandatory if there are no other digital connectors (Display Port, HDMI).
7.
HDMI connector for connecting a computer, laptop, TV tuner and other devices, it is desirable to have such a connector.
9.
A 3.5 mm audio jack for connecting audio to monitors with built-in speakers, external speakers or headphones is optional, but in some cases this solution may be convenient.
10.
The USB connector for connecting a USB hub built into the monitor is not available everywhere and is optional.
11.
USB connectors in monitors with a USB hub for connecting flash drives, mice, keyboards and other devices are optional, but in some cases it can be convenient.
17. Control buttons
Control buttons are used to adjust brightness, contrast and other parameters of the monitor.
Typically, the monitor is configured once and these keys are rarely used. But if the ambient lighting conditions are not constant, then the adjustment of the parameters may occur more often. If the control buttons are located on the front panel and are labeled, they will be more convenient to use. If there are no captions on the side or bottom panel, it will be difficult to guess where which button is. But in most cases you can get used to it.
Some, mostly more expensive monitors, may have a mini-joystick to navigate the menu. Many users note the convenience of this solution, even if the joystick is located on the back of the monitor.
18. Built-in speakers
Some monitors have built-in speakers. They are usually quite weak and do not differ in sound quality. Such a monitor is suitable for the office. For a home computer, it is advisable to purchase separate speakers.
19. Built-in TV tuner
Some monitors have a built-in TV tuner. Sometimes this can be convenient, since the monitor can also be used as a TV. But keep in mind that such a monitor itself will cost more and must support the required broadcast format in your region. As an alternative and more flexible option, you can buy a monitor with an HDMI connector and a separate inexpensive TV tuner suitable for your region.
20. Built-in webcam
Some monitors have a built-in webcam. This is absolutely not necessary, as you can purchase a separate high-quality webcam for a fairly reasonable price.
21. 3D support
Some monitors are specially adapted to use 3D technology. However, they still require the use of special glasses. I would say that this is all for an amateur and the level of development of this technology is still not high enough. Usually it all comes down to watching several films in this format and understanding that in games 3D only interferes and slows down the computer. In addition, this effect can be achieved on a regular monitor using special 3D players and a video card driver.
22. Curved screen
Some monitors have a curved screen designed to provide a more immersive gaming experience. Usually these are models with a large screen (27-34 ″) elongated in width (21: 9).
Such monitors are more suitable for those who use a computer mainly for passing various story games. The image on the sides turns out to be a little blurry, which, when the monitor is placed close in a dark room, gives the effect of immersion in the game.
But such monitors are not universal, as they have a number of disadvantages. They are poorly suited for dynamic online shooters (wide and blurry screen), watching videos in a company (worse viewing angles), working with graphics (image distortion).
In addition, not all games support the 21: 9 aspect ratio and will not fill the entire screen, and the higher resolution imposes very strict requirements on the computer's performance.
23. Body color and material
With regard to color, the most versatile are monitors in black or black and silver, as they blend well with other computer devices, modern household appliances and the interior.
24. Stand design
Most monitors have a standard non-adjustable stand, which is usually sufficient. But if you want more room for adjusting the position of the screen, for example, turning it to watch video while sitting on the couch, then pay attention to the models with a more functional adjustable stand.
The very presence of a high-quality stand is pretty nice.
25. Wall mount
Some monitors have a VESA mount that allows you to mount it on a wall or any other surface using a special arm that can be adjusted in any direction.
Consider this when choosing, if you want to embody your design ideas.
The VESA mount can be 75 × 75 or 100 × 100 and in most cases allows you to mount the monitor panel on any universal bracket. However, some monitors may have design flaws that prevent the use of universal brackets and require only one specific bracket size. Be sure to check with the seller and in the reviews for these features.
26. Links
Dell P2717H Monitor
Monitor DELL U2412M
Dell P2217H Monitor
Choosing the diagonal of your LCD TV
Choosing an LCD TV should start with determining the size of its diagonal. LCD TVs with a diagonal of 19-20 inches will fit well in the kitchen or in the nursery, 26-37 inches would be optimal for a bedroom or a small living room, and for a home cinema, choose a TV with a diagonal of 40 inches or more.
Working Resolution: FullHD and HD Ready
One of the important technical characteristics of a TV is the resolution of the matrix. It is denoted by two numbers, the first of which indicates the number of pixels in the width of the screen, and the second in height. The higher the resolution, the more pixels, which means you will see a sharper image on the screen.
In the specification of many modern TV models, you can find the terms Full HD or HD Ready. Full HD corresponds to a resolution of 1920 x 1080 pixels and means that your TV screen will have at least 2 million pixels (five times more than in the picture of a regular TV signal). This is a high definition image format that allows you to watch HDTV format TV programs, videos from Blu-ray discs. For you, this means a crisp image with excellent detailing.
With a 1366x768 HD Ready TV, you can also receive HD signals, but your screen will average about 1 million pixels in pixels.
Brightness, contrast and viewing angle
Important indicators of the matrix of LCD TVs are brightness and contrast. The numbers of these parameters affect the quality of the reproduction of color tones and the comfort of watching TV in different lighting conditions. The width of the viewing angles will depend on how well you will see the image if you are not in front of the screen, but slightly from the side.
Let's start with brightness. The higher the number representing this parameter, the more freedom you will be in choosing the options for placing the LCD TV in the room. If you want to put your TV in front of a window or are going to watch it in bright electric light, for example, in the kitchen, choose the brighter model - from 450 to 500 cd / m2.
The TV contrast numbers indicate the difference between white pixels and black pixels. In the technical specifications, they are indicated by a ratio of the type 100: 1. this means that the brightest parts of the picture differ from the darkest by 100 times. This means that the higher the first number, the more shades you will see on the screen. There is another type of contrast - dynamic contrast. This figure is always higher than the static contrast numbers. This is the ability of the monitor to automatically change the brightness of the bright and the depth of the dark shades of the image. A high level of dynamic contrast visually greatly expands the color tint gamut of the image.
More often than not, several people watch TV at once. This means that it is usually convenient for them to be located not directly in front of the screen, but throughout the room. In this case, one should not forget - the wider the viewing angle of the TV, the more contrasting the image will be. Models with viewing angles below 170 degrees are suitable for single viewing only. If you have a large family or you like to watch movies with friends, choose a TV with viewing angles of 180 degrees or more.
Pixel response time
An important metric for an LCD TV is its pixel response time. The smaller it is, the faster the transparency of each pixel will change without loss of quality. The unit of measurement is milliseconds.
Why choose TVs with faster pixel response times becomes clear when watching dynamic scenes of films or computer games. With a pixel response time of more than 8ms, you will notice blurry details, as if a moving object had a trail. For large size TVs, the recommended pixel response time is 5ms or less.
Technology 100, which is used in some TV models, increases the amount of information that is displayed on the screen. The technology allows you to calculate intermediate frames. By adding an intermediate image to each original frame, an increase in the smoothness of the image is achieved.
A TV tuner is a device that decodes an incoming signal and converts it into a "readable" picture. Previously, the tuner was installed in all TVs. Now manufacturers leave the choice up to you - do you need a tuner and which one. For satellite or cable TV users, a TV tuner is not required. According to the type of connection, TV tuners are divided into built-in and external ones. By signal type, TV tuners are analog and digital.
The built-in tuner is the most common type of TV tuner. The main advantage is its invisibility and ease of use. All necessary connections are provided on the back or side of the TV.
External tuners have several advantages. First of all, you can independently choose the manufacturer and the types of formats supported by the TV tuner. Secondly, it is possible to upgrade or replace the tuner with a more modern model.
An analog tuner is installed by default on all LCD TVs. It receives the signal from the antenna and decodes it.
Digital tuners differ in the types of resolutions they support. The most widespread digital television standard now is DVB-T.
LCD TV interfaces
A TV today is not just a free-standing box with an antenna. This is a true multimedia center of the house, to which players, game consoles, camcorders and digital storage devices are connected. The more interfaces your LCD TV has, the more possibilities for its use will open before you.
Analog connectors: S-Video, composite, component and SCART are available in almost all modern TVs. But, the signal transmitted with their help is not of the highest quality. Therefore, if you want to use all the features of your TV, choose models with digital connectors. The DVI output will allow you to receive a video signal from a DVD player or computer. And if you want the best quality, you need HDMI.
14 milliseconds can be seen with the naked eye, these two racing cars are 14 milliseconds away.Many modern and older LCD TVs with longer response times display blur around fast moving objects, making them unacceptable for action scenarios, sports, video games, and just about any fast moving video. For example, when watching a baseball game on an older LCD TV, a comet-like tail may appear on the ball as it moves rapidly across the screen. This phenomenon is most common in budget LCDs, but blurring is generally a problem inherent in LCD technology. The reason this blurring effect is important to us as consumers is because high response times can completely ruin a beautiful picture, regardless of the contrast and brightness of the TV.
Manufacturers have now significantly improved response times.
The latest solution to this issue is to increase the frame rate of LCD panels, many LCD panels now double or quadruple the original standard from 60Hz to 120Hz and 240Hz. But since manufacturers are increasingly competing with each other in terms of technical innovations, the quality is thereby deteriorating. Manufacturing plants are more likely to deceive the consumer in technical indicators or do not specify the response time at all. That was with viewing angles, then brightness and contrast, and now response times.
One example of good response times is Sharp's Aqua line. These are very highly sensitive LCDs and have a response time of 4 milliseconds. Older LCD TVs had times between 12 and 16 milliseconds. Current Sony XBR and Bravia LCDs have a response time of 4 milliseconds and 120Hz or higher. Some Chinese LCD manufacturers are rumored to have response times over 20 or even 25 milliseconds.
Speaking about the various parameters of LCD monitors - and this topic is regularly raised not only in our articles, but also on almost any "hardware" site that touches on the subject of monitors - we can distinguish three levels of discussion of the problem.Level one, basic: isn't the manufacturer cheating on us? In general, the answer at the moment is completely banal: serious monitor manufacturers do not stoop to banal deception.
Level two, more interesting: what do the declared parameters really mean? In fact, it boils down to a discussion of the conditions under which these parameters are measured by manufacturers and what practical limitations these conditions impose on the applicability of the measurement results. For example, a good example would be the measurement of the response time according to the ISO 13406-2 standard, where it was defined as the sum of the switching times of the matrix from black to white and vice versa. Studies show that for all types of matrices, this particular transition takes the shortest time, while at transitions between shades of gray, the response time can be several times higher, which means that in reality the matrix will not look as fast as on paper. Nevertheless, this example cannot be attributed to the first level of discussion, since it cannot be said that the manufacturer is deceiving us anywhere: if we set the maximum contrast on the monitor and measure the switching time "black-white-black", then it will coincide with the declared ...
However, there is an even more interesting level, the third: the question of how certain parameters are perceived by our eyes. Without touching the monitors for now (we will deal with them below), I will give an example from acoustics: from a purely technical point of view, tube sound amplifiers have rather mediocre parameters (high level of harmonics, poor impulse characteristics, and so on), and in connection with them, talk about fidelity sound reproduction is simply not necessary. Nevertheless, many listeners, on the contrary, like the sound of tube technology - but not because it is objectively better than transistor technology (as I said, this is not so), but because the distortions it introduces are pleasing to the ear.
Of course, the conversation about the subtleties of perception comes when the parameters of the devices under discussion are good enough for such subtleties to have a noticeable effect. You can take computer audio speakers for ten dollars - whichever amplifier you connect them to, they will not sound better, because their own distortions certainly exceed any flaws in the amplifier. It is the same with monitors - while the response time of the matrices was tens of milliseconds, there was simply no point in discussing the features of image perception by the retina; now, when the response time has decreased to a few milliseconds, it suddenly turned out that the monitor's performance is not the passport performance, but its subjective perception by a person - is determined not only by milliseconds ...
In the article offered to your attention, I would like to discuss both some passport parameters of monitors - the features of their measurement by manufacturers, compliance with reality, and so on - but also some points related specifically to the peculiarities of human vision. This primarily concerns the response time of monitors.
Monitor response time and eye response time
For a long time, in many monitor reviews - but what can I say, and I myself am a sinner - one could come across the statement that as soon as the response time of LCD panels (real response time, and not a passport value, which, as we all know, when measured according to ISO13406 -2, to put it mildly, does not quite accurately reflect reality) will decrease to 2 ... 4 ms, then we can simply forget about this parameter, further decreasing it will not give anything new, and so we will stop noticing blurring.And now, such monitors have appeared - the latest models of gaming monitors on TN matrices with response time compensation quite provide the arithmetic mean (GtG) time of the order of a few milliseconds. We will not now discuss such things as RTC artifacts or inherent flaws in TN technology - it is only important for us that the above figures have really been achieved. However, if you put them next to a regular CRT monitor, many people will notice that the CRT is still faster.
Oddly enough, it does not follow from this that you have to wait for LCD monitors with a response of 1 ms, 0.5 ms ... That is, you can wait for them, but such panels by themselves will not solve the problem - moreover, subjectively they won't even be much different from modern 2 ... 4 ms panels. Because the problem here is no longer in the panel, but in the peculiarities of human vision.
Everyone knows about such a thing as the inertia of the retina. It is enough to look at a bright object for one or two seconds, then close your eyes - and for a few more seconds you will see a slowly fading "imprint" of the image of this object. Of course, the print will be rather vague, in fact, contour, but we are talking about such a long period of time as seconds. For about 10 ... 20 ms after the disappearance of the actual picture, the retina of our eye continues to store its entire image, and only then it quickly fades away, leaving only the contours of the brightest objects in the end.
In the case of CRT monitors, the inertia of the retina plays a positive role: thanks to it, we do not notice the flickering of the screen. The duration of the afterglow of the phosphor of modern tubes is about 1 ms, while the time of passage of the beam across the screen is 10 ms (with a vertical scan of 100 Hz), that is, if our vision were inertialess, we would see a light strip running from top to bottom with a width of only 1/10 screen height. This can be easily demonstrated by photographing a CRT monitor at different shutter speeds:
At a shutter speed of 1/50 sec (20 ms), we see a normal image occupying the entire screen.
When the shutter speed is reduced to 1/200 sec (5 ms), a wide dark band appears on the image - during this time, at 100 Hz sweep, the beam manages to bypass only half of the screen, while on the other half of the screen the phosphor has time to go out.
And finally, at a shutter speed of 1/800 sec (1.25 ms), we see a narrow light strip running across the screen, followed by a small and rapidly darkening trail, while the main part of the screen is simply black. The width of the light strip is precisely determined by the afterglow time of the phosphor.
On the one hand, this behavior of the phosphor forces us to use high frame rates on CRT monitors, and at least 85 Hz for modern tubes. On the other hand, it is the relatively short afterglow time of the phosphor that leads to the fact that any, even the fastest, modern LCD monitor is still slightly, but inferior in speed to the good old CRT.
Let's imagine a simple case - a white square moving on a black screen, say, as in one of the tests of the popular TFTTest program. Consider two adjacent frames, between which the square has moved one position from left to right:
In the picture, I tried to depict four consecutive "snapshots", the first and the last of which fall at the moments when the monitor displays two adjacent frames, and the two middle ones demonstrate how the monitor and our eye behave in the interval between frames.
In the case of a CRT monitor, the required square is regularly displayed when the first frame arrives, but after 1 ms (the afterglow time of the phosphor) it starts to fade out quickly and disappears from the screen long before the second frame arrives. However, due to the inertia of the retina, we continue to see this square for about 10 ms - by the beginning of the second frame it just starts to fade noticeably. At the moment the monitor draws the second frame, our brain receives two images - a white square in a new place, plus its imprint on the retina, which quickly fades away on the retina, in the old place.
Active matrix LCD monitors, unlike CRTs, do not flicker - the picture on them is preserved for the entire period between frames. On the one hand, this allows you not to worry about the frame rate (there is no screen flickering in any case, at any frequency), on the other ... look at the picture above. So, during the interval between frames, the image on the CRT monitor quickly faded, but on the LCD it remained unchanged. After the arrival of the second frame, our white square is displayed on the monitor in a new position, and the old frame fades out in 1 ... 2 ms (in fact, the pixel blanking time for modern fast TN matrices is the same as the afterglow time of a phosphor for a CRT). However, the retina of our eye stores an afterimage, which will fade out only 10 ms after the disappearance of the real image, and until then will be added to the new image. As a result, within about ten milliseconds after the arrival of the second frame, our brain receives two images at once - the real picture of the second frame from the monitor screen plus the imprint of the first frame superimposed on it. Why not the usual blurring? .. Only now the old picture is stored not by the slow matrix of the monitor, but by the slow retina of our own eye.
In short, when the intrinsic response time of an LCD monitor falls below 10 ms, further slowing it down is less effective than one might expect because retinal inertia begins to play a significant role. Moreover, even if we reduce the response time of the monitor to completely insignificant values, it will still subjectively seem slower than a CRT. The difference lies in the moment from which the storage time of the residual image on the retina is counted: in a CRT, this is the arrival time of the first frame plus 1 ms, and in the LCD, this is the arrival time of the second frame, which gives us a difference of the order of ten milliseconds.
The way to solve this problem is quite obvious - since the CRT seems to be fast due to the fact that most of the time between two successive frames its screen is black, which makes it possible for the afterimage on the retina to start to fade just in time for the arrival of a new frame, then in the LCD monitor to achieve the same effect, it is necessary to artificially insert additional black frames between the image frames.
This is exactly what BenQ decided to do when it introduced Black Frame Insertion (BFI) technology some time ago. It was assumed that a monitor equipped with it would insert additional black frames into the displayed image, thereby emulating the operation of a conventional CRT:
Interestingly, it was initially assumed that frames will be inserted by changing the image on the matrix, and not by extinguishing the backlight. This technology is quite acceptable for fast TN-matrices, however, on MVA- and PVA-matrices there would be a problem with their too long switching time to black and back: if for modern TN it is a few milliseconds, then even for the best monitors on * VA- matrices fluctuate around 10 ms - thus, for them the time required to insert a black frame simply exceeds the frame repetition period of the main image, and the BFI technology turns out to be unusable. In addition, the limitation on the maximum duration of the black frame is imposed not even by the repetition period of the image frames (16.7 ms with a standard LCD frame rate of 60 Hz), but rather by our eyes - if the duration of the black inserts is too long, the flicker of the monitor screen will be no less noticeable than on a CRT with a sweep of the same 60 Hz. It is unlikely that anyone will like it.
I would like to note in passing that talking about doubling the frame rate when using BFI, as some reviewers do, is still incorrect: the natural frequency of the matrix should increase according to the addition of black frames to the video stream, but the frame rate of the image still remains the same, from the point of view of the video card and nothing changes at all.
As a result, when BenQ presented its FP241WZ monitor on a 24 "PVA matrix, it really turned out to be not the promised insertion of black frames, but a technology similar in purpose, but completely different in implementation, which differs from the original one in that the black frame is not inserted behind at the expense of the matrix, and due to the control of the backlight lamps: at the right time, they simply go out for a short time.
Of course, for the implementation of BFI in this form, the response time of the matrix does not play any role at all, it can be used with equal success both on TN matrices and on any others. In the case of the FP241WZ, there are 16 independently controlled horizontal backlight lamps in its panel behind the matrix. Unlike CRTs, where (as we saw in the photographs with a short exposure), a light sweep stripe runs across the screen, in BFI, on the contrary, the stripe is dark - at each moment of time 15 out of 16 lamps are on, and one is extinguished. Thus, when BFI is operating, a narrow dark band runs across the FP241WZ screen for one frame duration:
The reasons for choosing such a scheme (extinguishing one of the lamps instead of a seemingly exactly emulating CRT ignition of one of the lamps, or extinguishing and lighting all lamps at the same time) are quite obvious: modern LCD monitors operate with a 60 Hz vertical scan, so an attempt to exactly emulate a CRT would result in severe flickering of the picture. A narrow dark strip, the movement of which is synchronized with the frame scan of the monitor (that is, at the moment before the extinguishing of each of the lamps, the area of the matrix above it showed the previous frame, and by the time this lamp is lit, a new frame will already be recorded in it) on the one hand, partly compensates the effect of retinal inertia described above, and on the other hand, does not lead to noticeable flickering of the image.
Of course, with such modulation of the backlight lamps, the maximum brightness of the monitor drops slightly - but, in general, this is not a problem, modern LCD monitors have a very good margin of brightness (in some models it can go up to 400 cd / m2).
Unfortunately, FP241WZ hasn’t had time to visit our laboratory yet, so in terms of practical application of the new technology, I can only refer to the article of the respected BeHardware website “ BenQ FP241WZ: 1rst LCD with screening" (in English). As Vincent Alzieu notes in it, the new technology does improve the subjective assessment of the monitor's reaction speed, however, despite the fact that only one backlight out of sixteen is off at a time, in some cases, the screen still flickers. it is possible - first of all, on large one-color fields.
Most likely, this is due to the still insufficient frame rate - as I wrote above, the switching of the backlight lamps is synchronized with it, that is, the full cycle takes 16.7 ms (60 Hz). The sensitivity of the human eye to flickering depends on many conditions (for example, suffice it to recall, say, that 100 Hz flickering of an ordinary fluorescent lamp with electromagnetic ballast is difficult to notice when looking directly at it, but easily - if it falls into the peripheral vision), so it is quite It seems reasonable to assume that the monitor still lacks vertical scanning frequency, although the use of as many as 16 backlight lamps gives a positive effect: as we well know from CRT monitors, if the entire screen flickered with the same frequency of 60 Hz, you should look closely to detect this no flicker would be required, but working behind such a monitor would be quite problematic.
The most reasonable way out of this situation is the transition in LCD monitors to a frame rate of 75 or even 85 Hz. Some of our readers may argue that many monitors already support 75 Hz - but, alas, I have to disappoint them, this support is done in the vast majority of cases only on paper: the monitor receives 75 frames per second from the computer, then simply throws out every fifth frame and continues to display the same 60 frames per second on its matrix. This behavior can be documented by photographing an object rapidly moving across the screen with a sufficiently long exposure (about 1/5 of a second - so that the camera has time to capture a dozen monitor frames): on many monitors at 60 Hz, the photo will show a uniform movement of the object across the screen, and at 75 Hz sweep, gaps will appear in it. Subjectively, this will feel like a loss of fluidity.
In addition to this obstacle - I am sure, easily overcome if there is such a desire on the part of monitor manufacturers - there is one more thing: with an increase in the frame rate, the required bandwidth of the interface through which the monitor is connected increases. In other words, to switch to 75 Hz sweep, monitors with working resolutions 1600x1200 and 1680x1050 will need to use dual-link Dual Link DVI, since the operating frequency of single-link Single Link DVI (165 MHz) will no longer be enough. This problem is not fundamental, but it imposes some restrictions on the compatibility of monitors with video cards, especially not too new ones.
Interestingly, increasing the frame rate by itself will reduce image blur at the same panel response time - and again the effect is related to the inertia of the retina. Suppose the picture manages to move a centimeter on the screen during the period of one frame at 60 Hz (16.7 ms), then, after changing the frame, the retina of our eye will capture a new picture plus the shadow of the old picture superimposed on it, shifted by a centimeter. If we increase the frame rate by half, then the eye will capture frames with an interval of not 16.7 ms, but approximately 8.3 ms, respectively, and the shift of two pictures, old and new, relative to each other will become half as much, that is, with from the point of view of the eye, the length of the train following the moving image will be halved. Obviously, ideally, at a very high frame rate, we will get exactly the same picture as we see in real life, without any additional artificial blur.
Here, however, one must understand that it is not enough to increase only the frame rate of the monitor, as was done in a CRT to combat screen flickering - it is necessary that all image frames are unique, otherwise there will be absolutely no point in increasing the frequency.
In games, this will lead to an interesting effect - since in most new products, even for modern video cards, a speed of 60 FPS is already considered quite a good indicator, raising the scanning frequency of an LCD monitor itself will not affect blurring until you set enough a powerful video card (capable of working in this game at a speed corresponding to the monitor scan), or do not lower the graphics quality of the game to a sufficiently low level. In other words, on LCD monitors with a real frame rate of 85 or 100 Hz, blurring in games will, albeit to a small extent, still depend on the speed of the video card - and we are used to thinking that blurring depends solely on the monitor.
The situation with films is even more complicated - no matter what video card you put on yourself, the frame rate in the film is still 25, maximum 30 frames / sec, that is, increasing the frame rate of the monitor itself will not have any effect on reducing blur in films. In principle, there is a way out of this situation: when playing a movie, you can programmatically calculate additional frames, which is an averaging between two real frames, and insert them into a video stream - by the way, this approach will reduce blurring in films even on existing monitors, because their frame scan is 60 Hz is at least twice the frame rate in films, that is, there is a margin.
Such a scheme has already been implemented in the Samsung LE4073BD 100 Hz TV - it has a DSP that automatically tries to calculate intermediate frames and inserts them into the video stream between the main ones. On the one hand, the LE4073BD really demonstrates noticeably less blur compared to TVs that do not have such a function, but, on the other hand, the new technology also gives an unexpected effect - the image begins to resemble cheap soap operas with their unnaturally smooth movements. Someone may like this, but experience shows that most people prefer a little blurring of a regular monitor, rather than the new "soapy effect" - especially since in films the blurring of modern LCD monitors is already somewhere on the border of perception.
Of course, in addition to these problems, purely technical obstacles will arise - raising the frame rate above 60 Hz will mean the need to use Dual Link DVI already on monitors with a resolution of 1680x1050.
To summarize, three main points can be noted:
a) When the real response time of the LCD monitor is less than 10 ms, its further decrease gives the effect weaker than expected due to the fact that the inertia of the retina begins to play a role. In CRT monitors, a black gap between frames gives the retina time to "light up", while in classic LCD monitors there is no such gap, frames follow continuously. Therefore, further efforts by manufacturers to increase the speed of monitors will be aimed not so much at reducing their passport response time, but at combating retinal inertia. Moreover, this problem affects not only LCD monitors, but also any other active matrix technologies in which the pixel glows continuously.
b) The most promising at the moment seems to be the technology of short-term extinguishing of backlight lamps, as in the BenQ FP241WZ - it is relatively easy to implement (the only drawback is the need for a large number and a certain configuration of backlight lamps, but for large monitors this is a completely solvable problem), suitable for all types of matrices and does not have any hard-to-eliminate drawbacks. Perhaps it will only be necessary to increase the sweep frequency of new monitors to 75 ... 85 Hz - but, perhaps, manufacturers will be able to solve the problem noted above with flickering noticeable on the FP241WZ and in other ways, so for the final conclusion it is worth waiting for other models to appear on the market. dimmed monitors.
c) Generally speaking, from the point of view of most users, modern monitors (on any type of matrix) are quite fast even without such technologies, so it is worth seriously waiting for the appearance of various models with backlight dimming unless something else suits you.
Display Lag (Input Lag)
The topic of frame display delay in some monitor models, which has recently been very widely discussed in various forums, is only at first glance similar to the topic of response time - in fact, it is a completely different effect. If, during normal blurring, the frame received on the monitor begins to be displayed instantly, but its full rendering takes some time, then with a delay between the receipt of the frame from the video card to the monitor and the start of its display, some time elapses, which is a multiple of the frame scan period of the monitor. In other words, the monitor has a frame buffer - ordinary RAM - storing one or more frames; when a new frame arrives from the video card, it is first written to the buffer, and only then displayed on the screen.Objectively measuring this delay is quite simple - you need to connect two monitors (CRT and LCD or two different LCDs) to two outputs of one video card in cloning mode, then start a timer on them, showing milliseconds, and take a series of photographs of the screens of these monitors. Then, if one of them has a delay, the values of the timers in the photos will differ by the amount of this delay - while one monitor shows the current value of the timer, the second will show the value that was several frames earlier. To obtain a reliable result, it is advisable to take at least a couple of dozen photographs, and then discard those of them that clearly fell at the time of the frame change. The diagram below shows the results of such measurements for a Samsung SyncMaster 215TW monitor (in comparison with an LCD monitor that has no delay), the horizontal axis shows the difference in timer readings on the screens of two monitors, the vertical axis shows the number of frames with such a difference:
A total of 20 photographs were taken, 4 of them were clearly at the time of the frame change (two values were superimposed on them in the image of the timers, one from the old frame, the second from the new one), two frames gave a difference of 63 ms, three frames - 33 ms, and 11 frames - 47 ms. Obviously, the correct result for the 215TW is a delay of 47 ms, which is about three frames.
Making a small digression, I note that it is worth with some skepticism about publications on forums, the authors of which claim an abnormally low or abnormally high latency specifically on their monitors. As a rule, they do not collect enough statistics, but take one frame - as you saw above, in some frames you can accidentally "catch" a value both higher and lower than the real one, and the longer the shutter speed set on the camera, the greater the likelihood of such an error ... To get the real numbers, you need to make a dozen or two frames and select the most common delay value.
However, these are all lyrics, to us, the buyers, are of little interest - well, you won't take timers on it before buying a monitor in a store? .. From a practical point of view, the question is much more interesting, does it even make sense to pay attention to this delay. As an example, we will consider the aforementioned SyncMaster 215TW with 47 ms latency - I do not know of monitors with large values, so this choice is quite reasonable.
If we consider the time of 47 ms in terms of the speed of a human reaction, then this is a fairly small interval - it is comparable to the time it takes for a signal to travel from the brain to the muscles along the nerve fibers. In medicine, such a term as "the time of a simple sensorimotor reaction" is adopted - the interval between the appearance of a signal that is simple enough for the brain to process a signal (for example, lighting a light bulb) and a muscle reaction (for example, pressing a button). On average, for a person, the time of PSMR is about 200 ... 250 ms, this includes the time for registering an event with the eye and transmitting information about it to the brain, the time for recognizing the event by the brain and the time for transmitting the command from the brain to the muscles. In principle, even in comparison with this figure, the delay of 47 ms does not look too large.
In ordinary office work, such a delay is simply impossible to notice. You can try for as long as you like to notice the difference between the movement of the mouse and the movement of the cursor on the screen - but the very time of processing these events by the brain and linking them with each other (note, tracking the movement of the cursor is a much more difficult task than tracking the lighting of a light bulb in the PSMR test, so that there is no longer any talk of a simple reaction, which means that the reaction time will be longer than for PSMR) is so long that 47 ms turns out to be a completely insignificant value.
However, on the forums, many users say that on the new monitor, the cursor movements feel like "wadded", they hardly hit the small buttons and icons the first time, and so on - and the delay, which was absent on the old monitor, is to blame for everything. present at the new.
In the meantime, most people are switching to new large monitors, either from 19 "models with a resolution of 1280x1024, or from CRT monitors altogether. Let's take, for example, the transition from 19 "LCD to the aforementioned 215TW: the horizontal resolution increases by about a third (from 1280 to 1680 pixels), which means that to move the mouse cursor from the left edge of the screen to the right, the mouse itself will have to be moved a greater distance - provided that its working resolution and settings remain the same. This is where the feeling of "cottoniness", slowness of movements appears - try to reduce the cursor speed by a third on your current monitor in the mouse driver settings, get exactly the same sensations.
Exactly the same with misses on the buttons after changing the monitor - our nervous system, regrettably to admit it, is too slow in order to fix with our eyes the moment "the cursor has reached the button" and transmit a nerve impulse to the finger pressing the left mouse button before , as the cursor leaves the button. Therefore, in fact, the accuracy of hitting the buttons is nothing more than the correctness of movements, when the brain knows in advance which movement of the hand corresponds to which movement of the cursor, and also with what delay after the start of this movement it is necessary to send a command to the finger so that when it presses the button mouse, the cursor was on the right button. Of course, when you change both the resolution and the physical size of the screen, all this adjustment turns out to be completely useless - the brain has to get used to new conditions, but at first, while it acts according to the old habit, you will indeed sometimes miss the buttons. Only the delay caused by the monitor has nothing to do with it. As in the previous experiment, the same effect can be achieved simply by changing the sensitivity of the mouse - if you increase it, at first you will "skip" the necessary buttons, if you decrease it, on the contrary, you will stop the cursor before reaching them. Of course, after a while the brain adapts to new conditions, and you will start hitting the buttons again.
Therefore, changing the monitor to a new one with a significantly different resolution or screen size, do not be too lazy to go into the mouse settings and experiment a little with its sensitivity. If you have an old mouse with a low optical resolution, then it will not be superfluous to think about buying a new, more sensitive one - it will move more smoothly when set in the high speed settings. Honestly, against the background of the cost of a new monitor, spending an extra $ 20 on a good mouse is not so ruinous.
So, we figured out the work, the next point is films. Theoretically, the problem here may arise due to the desynchronization of the sound (which goes without delays) and the image (which is delayed by the monitor for 47 ms). However, having experimented a little in any video editor, you can easily establish that a person notices desynchronization in films with a difference of the order of 200 ... 300 ms, that is, many times more than the monitor in question gives. While 47 ms is just a little more than the period of one frame of a film (at 25 frames per second, the period is, respectively, 40 ms), it is impossible to notice such a small difference between sound and image.
And finally, the most interesting is gaming, the only area in which, at least in some cases, latency introduced by the monitor can matter. However, it should be noted that many of those discussing the problem on the forums tend to exaggerate it too much here - for most people and in most games the notorious 47 ms does not play any role. Perhaps, with the exception of a situation when in a multiplayer "shooter" you and your opponent see each other at the same time - in this case, reaction speed will really play a role, and the additional delay of 47 ms can become significant. If you already notice the enemy half a second later than he does you, then some milliseconds will not save the situation.
It should be noted that the monitor delay does not affect either the accuracy of aiming in FPS games, or the accuracy of cornering in auto racing ... In all these cases, the same alignment of movements works - our nervous system does not have time to work at such a speed , in order to press the "fire" button exactly at the moment when the sight is aimed at the enemy, but it perfectly adapts to a variety of conditions and, in particular, to the need to give your finger the command "press!" at the moment when the sight has not yet reached the enemy. Therefore, any additional delays of a short duration simply force the brain to rebuild a little under the new conditions - moreover, if a person who is accustomed to a monitor with a delay is transferred to a model without delay, he will have to get used to it in the same way, and the first quarter of an hour a new monitor he will find it suspiciously uncomfortable.
And, finally, I have already come across stories on the forums several times that it is impossible to play games on a new monitor due to the notorious delay, which ultimately boiled down to the fact that a person, reseeding an old monitor from a resolution of 1280x1024 to a 1680x1050 new one, is simply I didn’t think that his old video card in this resolution would not work too fast. So, when reading the forums, be careful - as a rule, you do not know anything about the level of technical literacy of those who write there, and you cannot tell in advance whether things that are obvious to you are just as obvious to them.
The situation with the discussion of monitor latencies is aggravated by two more points, to one degree or another inherent in most people. Firstly, many people are prone to overly complex attempts to explain simple phenomena - they prefer to believe that the bright point in the sky is a UFO, and not an ordinary meteorological balloon, that strange shadows in NASA's lunar photos indicate not the unevenness of the lunar landscape, but that that humans have never gone to the moon, and so on. Actually, any person interested in the activities of ufologists and similar organizations will tell you that most of their so-called discoveries are the result not so much of the absence of simple “earthly” explanations for many of the phenomenon, as a reluctance to search for simple explanations at all, a priori passing to overly complex theories. Oddly enough the analogy between ufologists and buyers of monitors, but the latter, having got to the forum, often behave the same way - for the most part they do not even try to consider the fact that with a significant change in the resolution and diagonal of the monitor, the feeling of working with it will change completely outside depending on any latency, they jump straight to the discussion of how the generally negligible 47ms latency affects mouse cursor movement.
Secondly, people are prone to self-hypnosis. Try to take two bottles of different types of beer, obviously cheap and notoriously expensive, pour the same beer in them - the vast majority of people, having tried it, will say that beer tastes better in a bottle with a label of an expensive type of beer. Cover the labels with opaque tape - opinions will be divided equally. The problem here is that our brain cannot completely abstract from all sorts of external factors - when we see an expensive package, we already begin to subconsciously expect a higher quality of the contents of this package, and vice versa. To combat this, all any serious subjective comparisons are carried out according to the method of a blind test - when all the samples under study are numbered, and none of the experts taking part in testing until the end of the test knows how these numbers relate to real brands.
Roughly the same thing happens with the discussed topic of display lag. A person who has just bought or is just about to buy a new monitor goes to the forum on monitors, where he immediately discovers multi-page threads about latency, in which he is told about "wadded mouse movements", and about the fact that it is impossible to play on such a monitor, and many other horrors. And, of course, there are a number of people who claim that they see this delay with the eye. After reading all this, a person goes to the store and begins to examine the monitor of interest to him with the thought “there must be a delay, people see it!”. Of course, after a while he himself begins to see it - more precisely, he believes that he sees - after which he returns home from the store and writes to the forum "Yes, I watched this monitor, there really is a delay!" There are also more amusing cases - when people directly write something like “I've been sitting at the discussed monitor for two weeks, but only now, after reading the forum, I clearly saw a delay on it”.
Some time ago, videos posted on YouTube became popular, in which on two monitors standing side by side (working in desktop expansion mode) a window is dragged up and down with a mouse - and you can clearly see how much this window lags on the monitor with a delay. The videos, of course, are beautiful, but ... imagine: a monitor with a 60 Hz scan is filmed with a camera with its own scan of a 50 Hz matrix, then saved to a video file with a frame rate of 25 Hz, uploaded to YouTube, which may well recode it inside itself. times without telling us about it ... Do you think that after all these transformations, there is a lot left of the original? In my opinion, not very much. An attempt to view one of these videos frame by frame (saving it from YouTube and opening it in a video editor) demonstrated this especially clearly - at some moments the difference between the two captured monitors is noticeably more than the aforementioned 47 ms, at other moments the windows on them move synchronously, as if there is no delay ... In general, complete confusion, senseless and merciless.
So, let's draw a short conclusion:
a) In some monitors, display delay is objectively present, the maximum reliably recorded value is 47 ms.
b) A delay of this magnitude cannot be noticed either in normal work or in films. In games, it can be essential at some points for well-trained players, but in most cases and for most people it is invisible in games as well.
c) As a rule, discomfort when changing the monitor to a model with a larger diagonal and resolution arises from insufficient speed or sensitivity of the mouse, insufficient speed of the video card, as well as the change in screen size itself. However, many people, after reading the forums too much, a priori attribute any discomfort on the new monitor to display lag problems.
In a nutshell: theoretically the problem exists, but its practical significance is greatly exaggerated. The vast majority of people will never notice a delay of 47 ms anywhere, not to mention lower latency values.
Contrast: passport, real and dynamic
Perhaps, the statement “the contrast of a good CRT monitor is higher than the contrast of an LCD monitor” has long been perceived by many people as an a priori truth that does not require additional proof - yet we see how noticeably the black background glows in the dark on the LCD screen. No, I'm not going to completely refute this statement, it is difficult to refute what you see perfectly with your own eyes, even sitting at the latest S-PVA matrix with a passport contrast ratio of 1000: 1.Passport contrast, as a rule, is measured by the manufacturers not of the monitors themselves, but of LCD matrices, on a special stand, when a certain signal is sent and a certain level of backlight brightness. It is equal to the ratio of the level of white to the level of black.
In ready-made monitors, the picture is first of all complicated by the fact that the black level is determined not only by the characteristics of the matrix, but also - sometimes - by the settings of the monitor itself, primarily in models where the brightness is controlled by the matrix, and not by backlight lamps. In this case, the contrast of the monitor may turn out to be much lower than the passport contrast of the matrix, if it is not adjusted too accurately. This effect can be clearly seen on Sony monitors, which have two brightness controls at once - both by the matrix and by the lamps - in them, when the brightness of the matrix is increased above 50%, the black color quickly turns into gray.
Here I would like to note once again that the opinion that the passport contrast can be increased due to the brightness of the backlight - and allegedly that is why many monitor manufacturers put such powerful lamps in them - is completely mistaken. With an increase in the brightness of the backlight, both the white level and the black level grow at the same rate, which means that their ratio, which is the contrast, does not change. It is impossible to increase the brightness level of the white color due to the backlight alone without increasing the brightness level of the black one.
However, all this has already been said many times before, so let's move on to considering other issues.
Undoubtedly, the passport contrast of modern LCD monitors is still not high enough to compete successfully with good CRT monitors in this parameter - in the dark, their screens still glow noticeably, even if the picture is completely black. But after all, we most often use monitors not in the dark, but even in daylight, sometimes quite bright. Obviously, in this case, the real contrast observed by us will differ from the passport one measured in the semi-darkness of the laboratory - the external light reflected by it will be added to the own glow of the monitor screen.
Above is a photo of two monitors standing side by side - a Samsung SyncMaster 950p + CRT monitor and a SyncMaster 215TW LCD monitor. Both are off, outside lighting is normal daylight on a cloudy day. It is clearly seen that the screen of a CRT monitor under ambient light turns out to be not only lighter, but much lighter than the screen of an LCD monitor - a situation exactly opposite to what we observe in the dark and with the monitors turned on.
The explanation is very simple - the phosphor used in cathode-ray tubes itself has a light gray color. To darken the screen, a tint film is applied to its glass - since the intrinsic glow of the phosphor passes through this film once, and the external light twice (the first time on the way to the phosphor, the second time, reflected from the phosphor, on the way out, to our eye) , then the latter is weakened by the film much more than the former.
Nevertheless, it is not possible to make a completely black screen on a CRT - as the transparency of the film decreases, it is necessary to increase the brightness of the glow of the phosphor, because the film also weakens it. And this brightness in a CRT is limited at a rather modest level, since if the current of the electron beam is increased too much, its focusing is greatly deteriorated, the image becomes indistinct, blurry. For this reason, the maximum reasonable brightness of CRT monitors does not exceed 150 cd / m2.
In the LCD matrix, on the other hand, there is practically nothing to reflect external light from, there is no phosphor in it, only layers of glass, polarizers and liquid crystals. Of course, some small part of the light is reflected from the outer surface of the screen, but most of it freely passes inward and is lost there forever. Therefore, in daylight, the screen of an off LCD monitor looks almost black.
So, in daylight and the monitors are off, the CRT screen is much lighter than the LCD screen. If we turn on both monitors, then the LCD, due to the lower passport contrast, will receive a greater increase in the black level than a CRT - but even so, it will still remain darker than a CRT. If we now close the curtains, "turning off" the daylight, then the situation will change to the opposite, and the CRT will have a deeper black color.
Thus, the real contrast of monitors depends on the ambient light: the higher it is, the more advantageous the LCD monitors are, even in bright light the picture on them remains contrasting, while on a CRT it noticeably fades. In the dark, on the contrary, the advantage is on the side of the CRT.
By the way, this is partly based on the good appearance - at least on the showcase - of monitors with a glossy screen surface. A regular matte coating scatters light incident on it in all directions, while a glossy one reflects it purposefully, like a regular mirror - therefore, if the light source is not located directly behind you, then the matrix with a glossy coating will look more contrasting than with a matte one. Alas, if the light source is suddenly behind you, the picture changes radically - the matte screen still scatters light more or less evenly, but the glossy one will reflect it exactly in your eyes.
It should be noted that all these considerations apply not only to LCD and CRT monitors, but also to other display technologies - for example, the SED panels promised to us by Toshiba and Canon in the near future, having a fantastic passport contrast ratio of 100,000: 1 (in other words, black the color on them in the dark is completely black), in real life in daylight they will fade in the same way as a CRT. They use the same phosphor that glows when it is bombarded with an electron beam, a black tint film is also installed in front of it, but if the defocusing of the beam interfered in the CRT (thereby increasing the contrast), then in SED this will be hindered by a noticeably decreasing the beam current is the life of the emitter cathodes.
However, recently, LCD monitors have appeared on the market with unusually high values of the declared passport contrast - up to 3000: 1 - and at the same time using the same matrices as monitors with more familiar numbers in the specifications. The explanation for this lies in the fact that values so large by LCD standards correspond not to “normal” contrast, but to the so-called dynamic contrast.
The idea, in general, is simple: in any film there are both light scenes and dark ones. In both cases, our eye perceives the brightness of the entire picture as a whole, that is, if most of the screen is light, then the black level in a few dark areas does not matter much, and vice versa. Therefore, it seems quite reasonable to automatically adjust the brightness of the backlight depending on the image on the screen - on dark scenes, the backlight can be dimmed, thereby making them even darker, on light scenes, on the contrary, bring it to maximum brightness. It is this automatic adjustment that is called "dynamic contrast".
The official figures of dynamic contrast are obtained very simply: the white level is measured at the maximum brightness of the backlight, the black level - at the minimum. As a result, if the matrix has a passport contrast ratio of 1000: 1, and the monitor electronics allows you to automatically change the brightness of the backlight three times, then the final dynamic contrast ratio will be equal to 3000: 1.
It should be understood that the dynamic contrast mode is suitable only for films, and maybe even for games - and even then, in the latter, players rather prefer to raise the brightness in dark scenes in order to more easily navigate what is happening, and not lower it. For normal operation, automatic brightness control depending on the image displayed on the screen is not only useless, but simply extremely annoying.
Of course, at each moment of time, the screen contrast - the ratio of the white level to the black level - does not exceed the passport static contrast of the monitor, however, as mentioned above, in light scenes the black level is not too important for the eye, and in dark scenes, on the contrary, the white level so automatic brightness control in movies is quite useful and really gives the impression of a monitor with a noticeably increased dynamic range.
The only drawback of the technology is that the brightness is controlled as a whole for the entire screen, so in scenes combining light and dark objects in equal proportions, the monitor will simply expose some average brightness. Dynamic contrast will also give nothing in dark scenes with separate small very bright objects (for example, a night street with lanterns) - since the general background will be dark, the monitor will reduce the brightness to a minimum, thus dimming bright objects. However, as mentioned above, due to the peculiarities of our perception, these shortcomings are hardly noticeable and in any case are less significant than the insufficient contrast of conventional monitors. So, in general, the new technology should appeal to many users.
Color rendering: color gamut and LED backlight
A little more than two years ago in the article "Parameters of modern LCD monitors" I wrote that such a parameter as color gamut, in general, is insignificant for monitors - simply because it is the same for all monitors. Fortunately, since then the situation has changed for the better - models of monitors with increased color gamut began to appear on the market.So what exactly is color gamut?
As you know, a person sees light in the wavelength range from about 380 to 700 nm, from violet to red. Four types of detectors act as light-sensitive elements in our eye - one type of rods and three types of cones. The rods have excellent sensitivity, but they do not distinguish between different wavelengths at all, they perceive the entire range as a whole, which gives us black and white vision. Cones, on the contrary, have a significantly lower sensitivity (and therefore stop working at dusk), but with sufficient illumination they endow us with color vision - each of the three types of cones is sensitive to its own wavelength range. If a ray of monochromatic light with a wavelength of, say, 400 nm hits our eye, then only one type of cones will react to it, which is responsible for the blue color. Thus, different types of cones perform approximately the same function as RGB filters facing the sensor of a digital camera.
Although it seems at first glance that our color vision can be easily described by three numbers, each of which will correspond to the level of red, green or blue, this is not the case. As experiments carried out at the beginning of the last century have shown, the processing of information by our eye and our brain is less unambiguous, and if we try to describe color perception in three coordinates (red, green, blue), it turns out that the eye can perceive without any problems colors for which, in such a system, the value of red turns out to be ... negative. In other words, it is impossible to fully describe human vision in an RGB system - in fact, the spectral sensitivity curves of different types of cones are somewhat more complicated.
As a result of experiments, a system was created that describes the entire range of colors perceived by our eyes. Its graphical display is called the CIE diagram and is shown in the figure above. Inside the shaded area are all the colors perceived by our eye; the contour of this area corresponds to pure, monochromatic colors, and the inner area, respectively, non-monochromatic, up to white (it is marked with a white point; in fact, "white" from the point of view of the eye is a relative concept, depending on the conditions we can consider white colors that actually differ from each other; on the CIE diagram, the so-called "point of the flat spectrum" is usually marked as a white point, having coordinates x = y = 1/3; under normal conditions, the corresponding color will seem very cold, bluish).
With the help of a CIE chart, any color perceived by the human eye can be indicated using two numbers, coordinates on the horizontal and vertical axes of the chart: x and y. But this is not surprising, but the fact that we can recreate any color using a set of several monochromatic colors, mixing them in a certain proportion - our eye is completely indifferent to what spectrum the light that got into it actually had, the only thing that matters is how each type of receptor, rods, and cones got excited.
If human vision were successfully described by the RGB model, then to emulate any of the colors that the eye could only see, it would be enough to take three sources, red, green and blue, and mix them in the desired proportions. However, as mentioned above, in fact we see more colors than can be described in RGB, so in practice the problem is the opposite: having three sources of different colors, what other colors can we get by mixing them?
The answer is very simple and clear: if you put down the points with the coordinates of these colors on the CIE diagram, then everything that can be obtained by mixing them will lie inside a triangle with vertices at these points. It is this triangle that is called "color gamut".
The maximum possible color gamut for a system with three basic colors is provided by the so-called laser display (see above in the figure), the basic colors of which are formed by three lasers, red, green and blue. The laser has a very narrow emission spectrum, it has excellent monochromaticity, so the coordinates of the corresponding base colors will lie exactly on the border of the diagram. It is impossible to take them out, outside the border - this is a non-physical area, the coordinates of the points in it do not correspond to any light, but any shift of points inside the diagram will lead to a decrease in the area of the corresponding triangle and, accordingly, to a decrease in the color gamut.
As can be clearly seen from the figure, even a laser display is not able to reproduce all the colors that the human eye sees, although it is quite close to this. It is possible to increase the color gamut only by using a larger number of basic colors (four, five, and so on), or by creating some hypothetical system that can "on the fly" change the coordinates of its basic colors - however, if the former is simply technically difficult at the moment, then the second is generally unrealizable.
However, it's too early for us to grieve over the shortcomings of laser displays anyway: we don't have them yet, but what we have demonstrates a color gamut that is very inferior to laser displays. In other words, in real monitors, both in CRT and LCD (with the exception of some models, which will be discussed below), the spectrum of each of the basic colors is quite far from monochromatic - in terms of the CIE diagram, this means that the vertices of the triangle will move from the boundaries of the diagram are closer to its center, and the area of the triangle will noticeably decrease.
Above in the picture, two triangles are drawn - for a laser display and the so-called sRGB. In short, the latter corresponds to the typical color gamut of modern LCD and CRT monitors. A sad picture, isn't it? I'm afraid we won't be able to see it yet ...
The reason for this - in the case of LCD monitors - is the extremely poor spectrum of LCD backlight lamps. As such, cold cathode fluorescent lamps (CCFL) are used - the discharge burning in them gives radiation in the ultraviolet spectrum, which is converted into ordinary white light by a phosphor applied to the walls of the lamp bulb.
In nature, the source of light for us is usually various incandescent bodies, primarily our Sun. The radiation spectrum of such a body is described by Planck's law, but the main thing is that it is continuous, continuous, all wavelengths are present in it, and the radiation intensities at close wavelengths differ slightly.
A fluorescent lamp, like other gas-discharge light sources, gives a line spectrum, in which there is no radiation at all at some wavelengths, and the intensities of the spectral regions separated by only a few nanometers from each other can differ by tens or hundreds of times. Since our eye is completely insensitive to a specific type of spectrum, from its point of view, both the Sun and the fluorescent lamp give exactly the same light. However, in the monitor, everything turns out to be somewhat more complicated ...
So, a few fluorescent lamps behind the LCD are shining through it. On the reverse side of the matrix there is a grating of multi-colored filters - red, green and blue - that form a triad of subpixels. Each filter cuts out from the lamp light a piece of the spectrum corresponding to its bandwidth - and, as we remember, to obtain maximum color gamut, this piece should be as narrow as possible. However, let's imagine that at a wavelength of 620 nm in the spectrum of the backlight lamp has a peak intensity ... well, let it be 100 arbitrary units. Then, for the red subpixel, we put a filter with a maximum transmission at the same 620 nm and, it would seem, we get the first vertex of the color gamut triangle, which lies neatly on the border of the diagram. Seemingly.
The phosphor of even modern fluorescent lamps is a rather capricious thing, we cannot control its spectrum at will, we can only choose from the known chemistry of a set of phosphors the one that more or less meets our needs. And the best one that we can choose has in its spectrum another peak with a height of the same 100 arbitrary units at a wavelength of 575 nm (this will be yellow). Our red filter with a maximum at 620 nm at this point has a transmittance of, say, 1/10 of the maximum.
What does this mean? That at the output of the filter we get not one wavelength, but two at once: 620 nm with an intensity of 100 conventional units and 575 nm with an intensity of 100 * 1/10 (the intensity in the lamp spectrum line is multiplied by the filter transmittance at a given wavelength), then there are 10 conventional units. In general, not so little.
Thus, because of the "extra" peak in the lamp spectrum, partially breaking through the filter, instead of monochromatic red, we got polychromatic - red with an admixture of yellow. On the CIE diagram, this means that the corresponding vertex of the gamut triangle has moved upward from the bottom edge of the diagram, closer to yellow shades, decreasing the area of the gamut triangle.
However, as you know, it is better to see once than hear five times. To see what was described above, I turned to the Plasma Physics Department of the N.N. Skobeltsyn, and soon an automated spectrographic system was at my disposal. It was designed to study and control the growth processes of artificial diamond films in microwave plasma based on the emission spectra of the plasma, so it will probably cope with some trivial LCD monitor without difficulty.
We turn on the system (a large and angular black box is a Solar TII MS3504i monochromator, on the left you can see its input port, opposite which a light guide with an optical system is fixed, on the right you can see an orange cylinder of a photosensor attached to the output port of the monochromator; on top is the system's power supply) ...
We install the input optical system to the required height and connect the second end of the fiber to it ...
And finally, we place it in front of the monitor. The entire system is controlled by a computer, so that the process of taking a spectrum in the entire range of interest to us (from 380 to 700 nm) is completed in just a couple of minutes:
The horizontal axis of the graph is the wavelength in angstroms (10 A = 1 nm), the vertical is the intensity in some arbitrary units. For greater clarity, the graph is painted in colors according to the wavelengths - as our eyes perceive them.
The test monitor in this case was Samsung SyncMaster 913N, a fairly old budget model on a TN matrix, but in general it does not matter - the same lamps with the same spectrum that are in it are used in the vast majority of other modern LCD monitors.
So what do we see on the spectrum? Namely, what was described in the words above: in addition to three distinct high peaks corresponding to the blue, red and green subpixels, we also see some completely extra garbage in the region of 570 ... 600 nm and 480 ... 500 nm. It is these extra peaks that shift the vertices of the color gamut triangle deep into the CIE diagram.
Of course, the best way to deal with this may be to abandon CCFL altogether - and some manufacturers have done just that, for example, Samsung with its SynsMaster XL20 monitor. In it, instead of fluorescent lamps, a block of LEDs of three colors - red, blue and green is used as a backlight (that's right, because the use of white LEDs does not make sense, because we will still cut out red, green and blue colors from the backlight spectrum with a filter) ... Each of the LEDs has a neat, flat spectrum that matches exactly the bandwidth of the corresponding filter and does not have any unnecessary sidebands:
Nice to see, isn't it?
Of course, the strip of each of the LEDs is wide enough, their radiation cannot be called strictly monochromatic, so it will not work to compete with a laser display, but when compared with the CCFL spectrum, it is a very pleasant picture, in which neat smooth minima in those two areas where CCFL had absolutely extra picks. It is also interesting that the position of the maxima of all three peaks has shifted slightly - with the red now noticeably closer to the edge of the visible spectrum, which will also have a positive effect on the color gamut.
And here, in fact, is the color gamut. We see that the coverage triangle of the SyncMaster 913N practically does not differ from the modest sRGB, and in comparison with the coverage of the human eye, green suffers most of all in it. But the XL20's color gamut is difficult to confuse with sRGB - it easily captures much more shades of green and blue-green colors, as well as deep reds. It's certainly not a laser display, but it's impressive.
However, we will not see home monitors with LED backlight for a long time. Even the SyncMaster XL20, which is slated to start sales this spring, will cost about $ 2,000 with a 20 "screen diagonal, and the 21" NEC SpectraView Reference 21 LED costs three times that amount - only printers are used to such prices for monitors (for which both of these models are primarily intended), but clearly not home users.
However, do not despair - there is hope for you and me too. It consists in the appearance on the market of monitors with backlighting on all the same fluorescent lamps, but with a new phosphor, in which unnecessary peaks in the spectrum are partially suppressed. These lamps are not as good as LEDs, but they are already noticeably superior to older lamps - the color gamut they provide is approximately halfway between the coverage of models on old lamps and models with LED backlighting.
For a numerical comparison of the color gamut, it is customary to indicate the percentage of coverage of a given monitor from one of the standard gamuts; sRGB is quite small, so NTSC is often used as the standard color gamut for comparison. Regular sRGB monitors have 72% NTSC color gamut, monitors with enhanced backlighting 97% NTSC, and LED backlit monitors 114% NTSC.
What does the increased color gamut give us? Manufacturers of LED-backlit monitors in their press releases usually place photographs of new monitors next to old ones, simply increasing the saturation of colors on new ones - this is not entirely true, because in fact, on new monitors, the saturation of only those colors that go beyond the color limits is improved. coverage of old monitors. But, of course, looking at the above press releases on your old monitor, you will never see this difference, because your monitor cannot reproduce these colors anyway. It's like trying to watch a color TV show in black and white. Although, manufacturers can also be understood - do they need to somehow reflect the advantages of new models in press releases? ..
In practice, however, there is a difference - I cannot say that it is fundamental, but unambiguously speaking in favor of models with an increased color gamut. It is expressed in a very clean and deep red and green color - if you switch back to the good old CCFL after a long work on a monitor with LED backlighting, at first you just want to add color saturation to it, until you understand that it will absolutely not help him in any way , red and green will remain somewhat dull and dirty in comparison with the "LED" monitor.
Unfortunately, so far the distribution of models with improved backlight lamps is not going quite as we would like - for example, Samsung started it with the SyncMaster 931C model on a TN matrix. Of course, budget monitors on TN will also benefit from an increased color gamut, but hardly anyone takes such models for working with color because of the frankly bad viewing angles. However, all the main manufacturers of LCD panels - LG.Philips LCD, AU Optronics and Samsung - already have S-IPS, MVA and S-PVA panels with a diagonal of 26-27 "and new backlight lamps.
In the long term, however, lamps with new phosphors will undoubtedly completely replace the old ones - and we will finally go beyond the modest coverage of sRGB, for the first time since the existence of color computer monitors.
Color rendering: color temperature
In the previous section I mentioned in passing that the concept of "white color" is subjective and depends on external conditions, now I would like to reveal this topic in a little more detail.So, in fact, there is no standard white color. One could take a flat spectrum as a standard (that is, one for which the intensities in the optical range are the same at all wavelengths), but there is one problem - in most cases for the human eye it will not look white, but very cold, with a bluish tint ...
The fact is that, just as in a camera, you can adjust the white balance, so our brain adjusts this balance for itself, depending on the ambient light. The light of an incandescent light bulb in the evening at home seems to us only slightly yellowish, although the same lamp, lit in a light shade on a fine sunny day, already looks completely yellow - because in both cases our brain adjusts its white balance to the prevailing lighting, and in these cases it is different ...
It is customary to denote the desired white color through the concept of "color temperature" - this is the temperature to which an absolutely black body must be heated in order for the light emitted by it to look the desired way. Let's say the surface of the Sun has a temperature of about 6000 K - and indeed, the color temperature of sunlight on a clear day is defined as 6000 K. The filament of an incandescent lamp has a temperature of about 2700 K - and the color temperature of its light is also 2700 K. It's funny that the higher the body temperature , the colder its light seems to us, because blue tones begin to prevail in it.
For sources with a line spectrum - for example, the CCFLs mentioned above - the concept of color temperature becomes somewhat more conventional, because it is, of course, impossible to compare their radiation with the continuous spectrum of a black body. So in their case, you have to rely on the perception of the spectrum by our eye, and from devices for measuring the color temperature of light sources to achieve the same cunning characteristics of color perception as in the eye.
In the case of monitors, we can adjust the color temperature from the menu: as a rule, there are three or four preset values (for some models - much more) and the ability to individually adjust the levels of basic RGB colors. The latter is inconvenient compared to CRT monitors, where it was the temperature that was adjusted, and not the RGB levels, but, unfortunately, for LCD monitors, except for some expensive models, this is the de facto standard. The purpose of adjusting the color temperature on the monitor is obvious - since ambient lighting is chosen as a reference for adjusting the white balance, the monitor must be adjusted so that the white looks white on it, and not bluish or reddish.
It is even more regrettable that for many monitors the color temperature varies greatly between different gray levels - it is obvious that gray differs from white very conditionally, only in brightness, so nothing prevents us from talking not about white balance, but about gray balance. and it will be even more correct. And many monitors also have different balance for different gray levels.
Above is a photograph of the screen of the ASUS PG191 monitor, on which four gray squares of different brightness are displayed - more precisely, there are three versions of this photograph put together. In the first of them, the gray balance is chosen according to the extreme right (fourth) square, in the second - according to the third, in the last - according to the second. None of them can be said to be correct, and the rest are not - in fact, they are all wrong, because the color temperature of the monitor should not depend in any way on what level of gray color we calculate it, but here it is clearly not so. This situation is corrected only by the hardware calibrator - but not by the monitor settings.
For this reason, in each of the articles for each of the monitors, I provide a table with the results of color temperature measurements for four different gray levels - and if they differ greatly from each other, the monitor image will be tinted in different tones, as in the picture above.
Ergonomics of the workspace and monitor setup
Despite the fact that this topic has no direct relation to the parameters of monitors, in the end of the article I would like to consider it, because, as practice shows, for many people, especially accustomed to CRT monitors, the process of initial setting up an LCD monitor can cause difficulties.First, the location in space. The monitor should be located at arm's length from the person working behind it, possibly slightly more - in case the monitor has a large screen size. You shouldn't put the monitor too close - so if you are going to buy a model with a small pixel size (17 "monitors with a resolution of 1280x1024, 20" 1600x1200 and 1680x1050, 23 "with a resolution of 1920x1200 ...), consider whether there will be an image for you it is too small and illegible. If you have such concerns, it is better to take a closer look at monitors with the same resolution, but with a larger diagonal, since from other measures of struggle there remains only the scaling of fonts and elements of the Windows interface (or the OS that you use), which is not in all applications programs gives a beautiful result.
The height of the monitor, ideally, should be adjusted so that the top edge of the screen is at eye level - in this case, when working, the gaze will be directed slightly downward, and the eyes are half-closed for eyelids, which will save them from drying out (as you know, during work, we blink too rarely) ... Many budget monitors, even 20 "and 22" models, use stands without height adjustment - if you have a choice, it is better to avoid such models, and in monitors with stand height adjustment pay attention to the range of this adjustment. However, almost all modern monitors allow you to remove the native stand from them and install a standard VESA bracket - and sometimes this opportunity is worth taking advantage of, because a good bracket gives not only the freedom to move the screen, but also the ability to install it to the height you need. starting from zero relative to the top of the table.
An important point is the lighting of the workplace. It is categorically contraindicated to work behind a monitor in complete darkness - a sharp transition between a bright screen and a dark background will greatly tire the eyes. For watching movies and playing games, a small background light is sufficient, for example, one table or wall lamp; for work, it is better to organize full-fledged lighting of the workplace. For lighting, you can use incandescent lamps or fluorescent lamps with electronic ballast (both compact, chambered for E14 or E27, and ordinary "tubes"), but fluorescent lamps with electromagnetic ballast should be avoided - these lamps flicker strongly at twice the frequency of the mains voltage , i.e. 100 Hz, this flicker can interfere with the sweep or self flickering of the monitor backlight lamps, which sometimes creates extremely unpleasant effects. In large office premises, blocks of fluorescent lamps are used, the lamps in which flicker in different phases (either by connecting different lamps to different phases of the supply network, or by installing phase-shifting chains), which significantly reduces the visibility of flickering. At home, where there is usually only one lamp, there is also only one way to combat flickering - the use of modern lamps with electronic ballast.
Having installed the monitor in the real space, you can connect it to the computer and continue the installation in the virtual one.
An LCD monitor, unlike a CRT, has exactly one resolution at which it works well. In all other resolutions, the LCD monitor does not work well - therefore, it is better to immediately set its native resolution in the video card settings. Here, of course, we must once again note the need to think before buying a monitor whether the native resolution of the selected model will seem too large or too small for you - and, if necessary, adjust your plans by choosing a model with a different screen diagonal or with a different resolution.
The frame rate of modern monitors is, by and large, the same for all - 60 Hz. Despite the formally declared frequencies of 75 Hz and even 85 Hz for many models, when they are installed, the monitor matrix usually continues to work at the same 60 Hz, and the monitor electronics simply discard the "extra" frames. Therefore, there is no point in chasing high frequencies: unlike CRTs, there is no flicker on LCD monitors.
If your monitor has two inputs, digital DVI-D and analog D-Sub, then it is better to use the first for work - it not only gives a better picture at high resolutions, but also simplifies the setup process. If only an analog input is available, then after connecting and setting the native resolution, you should open some clear contrasting image - for example, a page of text - and check if there are any unpleasant artifacts in the form of flickering, waves, noise, borders around symbols, etc. like that. If something similar is observed, press the auto-adjust button on the monitor for the signal; in many models it turns on automatically when the resolution is changed, but a smooth, low-contrast picture of the Windows desktop is not always enough for successful autotuning, so you have to start it manually again. When connecting via the digital input DVI-D, such problems do not arise, therefore, when buying a monitor, it is better to pay attention to the set of inputs it has and give preference to models with DVI-D.
Almost all modern monitors have default settings that give a very high brightness - about 200 cd / m2. This brightness is suitable for working on a sunny day, or for watching movies - but not for work: for comparison, the typical brightness of a CRT monitor is about 80 ... 100 cd / m2. Therefore, the first thing to do after turning on a new monitor is to set the desired brightness. The main thing is to do it without haste, without trying to get the perfect result in one movement, and even more so without trying to do it “like on an old monitor”; the problem is that the eye-candy of an old monitor doesn't mean fine-tuning and high-quality images — just that your eyes are accustomed to it. A person who has moved to a new monitor from an old CRT with a shrunken tube and a dim image may at first complain of excessive brightness and clarity - but if a month later you put the old CRT in front of him again, it turns out that now he cannot sit in front of it, because that the picture is too dim and dark.
For this reason, if your eyes feel discomfort when working with the monitor, you should try to change its settings gradually and in connection with each other - reduce the brightness and contrast a little, work more, if the discomfort remains, reduce them a little more ... Let's after each such a change, the eyes take time to get used to the picture.
In principle, there is a good trick that allows you to quickly adjust the brightness of an LCD monitor to an acceptable level: you need to put a sheet of white paper next to the screen and adjust the brightness and contrast of the monitor so that the brightness of the white color on it is close to the brightness of the sheet of paper. Of course, this technique assumes that your workplace is well lit.
It is also worth experimenting a little with the color temperature - ideally, it should be such that the white color on the monitor screen is perceived by the eye as white, and not bluish or reddish. However, this perception depends on the type of ambient lighting, while monitors are initially set up for some average conditions, and many models are also very inaccurately set up. Try changing the color temperature to a warmer or colder one, moving the sliders for adjusting the RGB levels in the monitor menu - this can also have a positive effect, especially if the default color temperature of the monitor is too high: the eyes react worse to cold shades than to warm ones.
Unfortunately, many users do not follow these generally simple recommendations - and as a result, multi-page topics are born in the forums in the spirit of "Help me choose a monitor that does not get tired of the eyes", where it comes right up to creating lists of monitors from which the eyes get tired. Gentlemen, I have worked with dozens of monitors, and my eyes did not get tired of any, except for a couple of ultra-budget models, which simply had problems with image clarity or a very crooked color reproduction setting. Because the eyes do not get tired from the monitor - but from its incorrect settings.
In forums, in such topics, sometimes it comes to ridiculous - the effect of flickering of backlight lamps is discussed (its frequency in modern monitors is usually 200 ... 250 Hz, which, of course, is not perceived by the eye at all) on vision, the influence of polarized light, the effect of too low or too high (to taste) contrast of modern LCD monitors, there was somehow even one topic in which the influence of the line spectrum of backlight lamps on vision was discussed. However, this, it seems, is already a topic for another article, an April Fool's ...
DIAGONAL
So, the first thing that will interest you is the size of the TV, or rather its diagonal. Do not forget that in a store, the diagonal is difficult to determine by eye due to the large space around. Meanwhile, a properly selected screen diagonal largely determines the comfort and impressions obtained from viewing. Traditionally, the size of the diagonal of the screen is measured in inches and is denoted, for example, like this: 32 ". It is easy to calculate it in centimeters: 1 inch = 2.54 cm. The diagonal of the TV screen must necessarily correspond to the size of the room in which it is planned to be installed. LG offers a variety of models to suit every taste and budget. For example, for a large living room, a curved screen or an 84-inch TV is perfect. It is important that both you and your guests are satisfied with the image, no matter from which corner of the room you look at it. For smaller rooms, for a bedroom or a nursery, a TV with a screen diagonal of 32 ”or more will be optimal. The optimal diagonal of a TV screen, according to experts, should be about 3 times less than the distance at which it is supposed to be watched. Some TVs show individual pixels and distorted colors when viewed too close. LG TVs are equipped with an IPS matrix, which allows you to transfer images without distorting the original shades, with maximum clarity and a wide viewing angle.
SCREEN RESOLUTION
The second important characteristic of any TV is screen resolution. .
Image quality depends on it. The screen of any LCD, LED or plasma TV consists of cells called pixels, the total number of which is called the screen resolution. It is expressed as two numbers, the first of which indicates the number of pixels horizontally and the second vertically, for example, 1920x1080. LG TVs offer incredible picture clarity. The high definition screen allows the TV to display crisp images with plenty of detail, even during fast moving scenes.
While most models were previously offered as the maximum resolution HDTV (English "High-Definition Television"), then today LG TVs are already produced with Ultra HD (4K) resolution and recently a TV with 8K resolution was introduced. 4K Ultra HD delivers incredible depth, clarity and detail, four times greater than Full HD screens.
LG makes innovative technologies available to every consumer so that everyone can enjoy impeccable quality and unique design. For Kazakhstani consumers, LG presents a wide range of 4K Ultra HD TVs, allowing them to make a choice depending on their needs.
Models of the UB820, UB830 and UB850 (,) series with diagonals from 125 to 140 cm are the most affordable of all LG 4K TVs. Quality LG TVs in these series have all the main features, including Smart TV functions and the new webOS platform, which was awarded the prestigious Red Dot Awards-2014 for the most user-friendly interface.
Ultra-high resolution displays crisp images while retaining every detail and nuance, while the built-in multi-channel front-firing speaker system delivers truly powerful room-filling sound for more immersive movie viewing combined with ULTRA HD images.
SMARTTV
LG Smart TV makes it easy to connect to premium content from multiple providers. Simple and functional, the Magic Remote saves time and lets you point, click, scroll and even talk with the remote to find exactly what you want, offering you a search for movies, apps, TV shows and web content. Navigation takes a minimum amount of time. Plus, using LG Smart TVs is more intuitive than ever. The new webOS user interface allows you to customize your home screen so that you can access the applications you use most often, as well as easily switch between them, remembering which application you last stopped on or picking up the latest updates. Some models, for example, are equipped with a special 2D to 3D converter from LG, which creates a new dimension in conventional video. You will hear more realistic surround sound if you pay attention to the model that is equipped with Virtual Surround Plus technology. This effect gives the impression that sound is pouring in from almost all directions. The smart energy saving function in the model will help you help nature by reducing energy consumption. This feature includes backlight control for dimming, video mute for audio-only playback, and Zero Standby, a feature that virtually turns the TV off and consumes no power. The range of models, diagonals and unique features is very wide.
MATRIX RESPONSE TIME
What is response time and how does it affect the quality of a TV? The response time of the matrix is the time it takes for the pixels of the monitor / TV / laptop display to change their color with the change of the image on the screen. The response time is measured in milliseconds, and the shorter this time, the better the device reproduces dynamic images in scenes in films and games, and thereby eliminates the visibility of trails behind moving objects on the screen. For comfortable viewing of news, for example, a screen with a response time of up to 8-10 ms is enough, but if you plan to watch movies or play modern games, you should choose models with a minimum indicator. The best to date is the response time in curved TVs, which is just 0.002ms - a result hundreds of times faster than LED TVs, which allows you to enjoy action scenes without blurring.
CONTRAST
Another characteristic of a TV screen that affects viewing comfort is picture contrast, which is the ratio of the brightness of the lightest to the darkest part. High contrast allows you to see more color tones and picture details. Conventional TVs use the standard 3 sub-pixel technology, so the color reproduction is different from reality. LG Electronics has developed a proprietary WRGB 4-color pixel technology for OLED TVs that reproduces realistic, crisp and rich colors with limitless picture contrast. With the unique idea of using an extra white sub-pixel, the LG OLED Curved TV displays more lifelike colors and accurate hues. The world's first 140cm curved OLED TV (model), with a revolutionary design, immerses you in the viewing experience and allows you to enjoy a variety of colors and contrasts. In addition, all the latest LG TVs are equipped with an IPS matrix. By maintaining a constant color temperature, natural tones and accurate color matching are ensured, without distortion. This LG development allows you to enjoy the true beauty of the picture and the accuracy of the tones across the screen, no matter what angle you look at it!
ANGLE OF VIEW
The picture quality can change dramatically depending on where you sit in relation to the screen. TV viewing angle is the angle at which you can watch TV without losing picture quality. IPS matrix is a unique feature of LG displays. The image on the TV screen is not distorted even when exposed to external influences such as pressing or tapping. IPS is a technology for performing a matrix of a liquid crystal screen, when the crystals are located parallel to each other along a single plane of the screen, and not spiral. Changing the orientation of the crystals helped to achieve one of the main advantages of IPS-matrices - the growth of the viewing angle up to 178 ° horizontally and vertically, in contrast to the TN matrix. In practice, the most important difference between an IPS matrix and a TN-TFT matrix is the increased contrast level due to the almost perfect display of black color. The picture is clearer. IPS-based screens do not distort or invert colors when viewed at an angle. The picture will always be bright and clear, providing the best work on the Internet, watching videos. This is a real breakthrough in image quality, but a more significant event in the tech world is the arrival of the first curved OLED TV. literally ushered in a new era in television design. The smoothly curved screen on LG's groundbreaking TV creates a more immersive viewing experience. the surface of the screen is equidistant from the viewer's eyes. This removes the problem of image distortion and degradation of detail at the edges.
SOUND
The built-in speaker system is present in almost any modern TV. Inexpensive TVs can only reproduce mono sound and use one or two speakers. More advanced ones are equipped with a built-in stereo system, in which the number of speakers can be from two to eight. The best audio technology available on LG TVs. For example, the latest generation of LG TVs in the series are equipped with audio technology from the real “gurus” in the field of sound reproduction - the company harman / kardon®. The harman / kardon® audio system delivers high-fidelity sound reproduction with deep bass and wide dynamic range. Simply put, this sound from the front speakers instantly fills the space, completely immersing the viewer in what is happening on the screen. So far, this effect of presence can only be felt in the cinema. The speakers distribute sound in multiple directions at once, creating 3D audio.
LG presents a huge range of TVs, from the smallest to the very largest, from the most affordable to premium TVs. LG TVs can be purchased in large stores of Kazakhstan retail chains "Technodom" , "Sulpak" , "Dream", "Fora", as well as in the company store Lg in Almaty (street Tole bi 216 B, corner of Rozybakiev street).
