Shall we play box? How to watch TV without harm to your health

How long to watch?

An adult can watch TV for 2–3 hours a day . But it is advisable that you spend no more than 1.5 hours in a row .
Young children should not watch TV for more than 30 minutes a day.

A child aged 3–7 years can sit in front of a screen for no more than an hour , and for children 7–13 years old 2 hours a day will be .

Click to enlarge. Infographics by Maria Klementieva

Is there any benefit from TV?

Of course, it’s not worth excluding television from a child’s world completely. There are also benefits from it:

1. Expanding your horizons . Through the screen you can get acquainted with different countries, traditions, cultures, and gain new knowledge in different areas. This can be a powerful source of inspiration and desire to explore the world.
2. Development of intelligence . With the help of modern technologies, children are presented with exciting information written in thick and boring encyclopedias. Few people are interested in studying such books, but learning with the help of video content is easy and enjoyable.
3. Enrichment of vocabulary . The child hears the correctly delivered speech of TV presenters and TV characters, learns many new words, the meaning of which he will certainly ask his parents questions about. It is only important to always answer them and get to the bottom of it.
4. Common interests with peers . Children who don’t watch TV at all risk becoming “black sheep” in children’s society. Not knowing popular characters from cartoons or TV shows, they do not maintain a conversation and feel excluded from the team. For very young children this is not critical; children find a common language in playing together. But the older the child, the more important it is for him to be “on the same wavelength” with his peers. And this cannot be ignored.

In what position?

The head should not tilt back - this puts extra stress on the cervical vertebrae - or lean forward - this leads to the appearance of a double chin and sagging facial contours.

Try not to sit cross-legged - this can cause blood stagnation in the veins of the lower extremities and increase the risk of varicose veins.

Change your position often . When watching TV while sitting, shift from toe to heel, move your feet in different directions.

Article on the topic

Pandora's Box. Why TV is addictive

Moral decay

Another proven harm of television: mass culture is not aimed at developing and educating people. Its goal is to make us worse than we really are.

Think about what is cultivated in popular TV shows, series and advertising? Greed, fear, sex - these are the main levers that the producers of these projects put pressure on.

It’s rare that a film can manage without the cultivation of violence (and, what’s worse, its approval). Successful heroines are mostly sexy beauties with model appearance. And the happy people on screen are fabulously rich, with endless possibilities. All this together creates a false picture of the world among TV viewers. They begin to feel like losers and begin to envy the on-screen heroes. They strive to adopt false life values ​​from the screen in order to be at least somehow similar to those distant beautiful images.

At the same time, there are catastrophically few worthwhile films and television programs that encourage children and adults to think about what is important, to realize themselves, and to become better. Unfortunately, negativity and base emotions are the most popular “product” on TV. And not a representation of a real happy life, which is available to each of us without “secrets of success” and “new products of the season.”

Where to put?

The safe distance from which you can watch TV depends on the screen diagonal and resolution . The larger the TV, the farther the viewer should sit. But at the same time, the higher the screen resolution, the less strain on the eyesight, so high-resolution TVs (FULL HD, ULTRA HD) can be viewed from a closer distance than those that support standard screen resolution (SD). For screens labeled HDReady, you must select the average value.

TVs. Part 2. Plasma or LCD, chassis, diagonal, motion transmission, color, effect on vision

Hello again, dear habra-people. The first part aroused some interest, so it was decided to continue this topic. I would like to say a special thank you to those who paid attention to the first part. I did not think that my modest article would arouse such considerable interest.

We can continue. In the second part, I would like to share my thoughts on the choice of TV diagonal for various applications, the choice of technology, as well as how frame interpolation affects the smoothness of movement and try to debunk some myths regarding modern TVs. Also, I want to touch on the topic of the influence of various TV parameters on vision.

After I figured out the hardware, I decided that now I need to find out what affects the image in practice and how, knowing this, you can choose a TV.

Chassis

We need to remember such a concept as the chassis. Roughly speaking, this is all the electronics inside the TV. TVs on the same chassis have exactly the same video path. TVs with the same chassis necessarily carry the same set of inputs and have exactly the same signal processing. Chassis models are most often described in service instructions, but they cannot be compared directly: the chassis does not have characteristics by which comparisons could be made. When LCD matrices are produced by only a few players in the market (these are Samsung, Sharp and LG), the chassis is developed by almost every TV manufacturer. Of the major players, only Sharp is not doing this (oddly enough, it produces the best matrices on the market and is unable to develop a chassis), which buys the chassis from Philips. Basically, the chassis differs from series to series (the lower the series, the simpler the chassis), one chassis model can cover several series (then TVs from different series will be similar). Philips, if I may say so, created an interesting incident this year - it built all TVs from the 6th to the 9th series on one chassis, which means that, among other things, all these TVs have one image processing processor that responds for frame interpolation. Philips calls different types of processing with beautiful marketing names “Perfect Pixel HD”, “Pixel Precise HD”, and if previously there were real differences in processing between these names, now all the differences have been erased. I understand why Philips left different names for essentially the same treatment - older series TVs should feel superior. But it's not fair.

LCD, Plasma - what to choose?

If you haven’t read part 1 of the article and don’t know the main differences between different image output technologies, matrices and different types of LCD backlighting, I advise you to read it.
If you are choosing a TV, you should first decide which technology to choose. And this is the hardest part. The sellers unanimously said that there was nothing other than LCD; on “advanced” video forums they only recommended plasma. Everything turned out to be a little simpler - everything has its own purpose and each technology is suitable for its task.

What factors influence the choice in favor of LCD

— You are watching TV in a bright room.
Plasma is essentially glass, and no matter how “cool” the anti-glare filter is, plasma behaves worse in bright light. Add to this the high brightness of LCD LED and you get the answer - if you watch TV in a bright room, you should pay attention to LCD.

— You want to use the TV as a monitor (Internet, image processing)

As you know, LCD has virtually no memory effect when the image “freezes” on the screen, so it is ideal as a technology for monitors. Plasma has a residual image effect. In addition, gradations on a plasma display occur using dithering, so near a clear grid of pixels you can’t see everything “moves.” Plasma is not suitable as a monitor.

— Do you want a small diagonal TV?

Small diagonals are where LCD reigns supreme. FullHD plasma starts only at 42″.

— Your eyes do not perceive the imaging technology of plasma TV

There are people (only a few percent) who are not suitable for plasma because they see flickering. If you see flickering, set the mode to 96 Hz, turn off all the lights (“energy-saving” lamps also have their own frequency and it can interfere with the plasma), change the settings if you are using a PC. Only then will it be possible to talk about “flickering”.

- Do you like oversaturated colors?

I do not belong to this category of people, but there are such people.

What factors influence the choice in favor of Plasma

— You want to watch mostly HD
Blu-Ray content, BD rips - it's all about plasma. These are her best friends and she brings out quality content the most.

- You often watch TV with the lights dimmed or in the dark

If light is plasma's main enemy, then darkness is its best friend. It is in the dark that the image reveals itself in full force.

— You choose a TV for home cinema

Cinema is what people buy plasma for. It is this that creates the “volume” effect of a 2D image, has a deep black level, is famous for its lack of flare, and has excellent contrast transitions.

— You need a large diagonal TV:

50″—65″ these are exactly the diagonals in which you should choose plasma. A 65″ LCD TV for home theater is a very strange choice.

- Do you like natural colors?

I do a little photography and have an idea of ​​what reference colors are. These are not at all dull, as you might think, but bright, rich and deep colors.

Diagonal selection:

It's time to choose the diagonal for your TV.
The choice of this diagonal is influenced by the following factors: - Distance to the TV. Attention - only distance, the size of the room does not affect the choice of diagonal. — Content permission. It is absolutely clear that the higher the clarity of the content, the closer you can watch TV. - Purpose. If you choose a TV for a home theater, this is one diagonal, a TV for the dacha is another. - Budget. If, as often happens, the budget is limited, it is not necessary to buy the recommended diagonal; you can buy a smaller one. There is such an organization: George Lucas's THX, which gives out picture certificates and sets standards in the field of television. It is her recommendations that I propose to use (especially since these are recommendations not of just THX, but of many, many companies and experts.

I present for your consideration a table of diagonals:

When I bought my first modern 42″ TV for viewing from 3 meters, this table would have shocked me, but not now. Now I realized that the diagonal tends to “shrink out” (when the TV appears large at first). Please note that the table is relevant when choosing a TV for a home theater. If you are not such a “gourmet” and choose a TV for a pleasant viewing of programs in the evening, you can pay attention to smaller diagonals. When choosing the THX-designated diagonal for 1080, the diagonal does not seem large, the eyes do not run around the screen and do not get tired at all.

One simple rule applies here: there can never be too many diagonals. If you are choosing a TV for a home theater and are not limited by budget, take the diagonal from the table.

What about the eyes?

So we come to the most common myth that has remained in our memory since the days of CRT.
This is due to the radiation generated by this type of TV. Modern TV lacks this. The myth says that the larger the diagonal of the TV, the more harmful it is to the eyes in the long run. It is mainly the accommodative muscle, which is responsible for focusing, that “breaks”. She stretches the lens so that the rays converge at the desired point. When the functions of the accommodative muscle are disrupted, a spasm of accommodation occurs and it becomes increasingly difficult for the eye to focus on distant objects. School-age children are at high risk of developing myopia. What causes vision damage when watching TV? In general, due to the same thing that causes it to deteriorate when reading a book, especially in dim light - the eye focuses at one distance, tenses, and the ability of the accommodative muscle is impaired. The muscle tenses the more, the closer and smaller the object on which you need to focus. What conclusions can be drawn from this? — The closer the distance to the TV, the more tired the eyes are and the higher the likelihood of visual impairment. But the dependence is not linear (that is, 2 meters is not 2 times more harmful than 1 meter), but rather exponential or close to it, and there is no big difference between 2 and 3 meters. — The smaller the object on which you need to focus, the more tired your eyes are and the greater the likelihood of disruption of accommodation functions. That is, in theory, a small diagonal is more harmful than a large one. I was unable to find research on this matter, but we can say with confidence that, all other things being equal, a large diagonal of an LCD or plasma TV is no more harmful than a small one.

Frame interpolation

Many users ask why fast movement of objects or panning looks smooth on some TVs, but not on others.
It’s worth starting with the fact that the 24 frames per second standard for the film industry was adopted in the first half of the 20th century, when the requirements for cinema were somewhat different and excessive waste of film was not welcomed. This “jerking” of the image is called a strobe. It is an absolute fact that 24 fps is not enough to convey fast-moving objects or panoramic camera movement. This means that if software processing is turned off, all televisions without exception will display this type of motion not in the best images. We are hostages of the standard. There are several real solutions to this problem, but they all boil down to increased frame rates. 1) Frame interpolation. Something that all modern TVs in the mid-price category can do to varying degrees of success. The TV analyzes 2 adjacent frames on the fly and draws another one or even 2 at its discretion. 2) HFR (high frame rate). Shooting initially in high frame format. It eliminates image processing artifacts by the TV processor, but requires special shooting, and most importantly, the media. The first and only film produced by HFR was The Hobbit: An Unexpected Journey. It is not yet clear to me what media it will be distributed on or whether it will be distributed in HFR at all. All methods of increasing the frame rate carry one serious drawback - the loss of the “cinema” quality of the image. The film looks unnatural and unusual. While the film world is at a crossroads - to shoot and watch in HFR or the usual frame rate. No one knows which path will be chosen. Personally, I watch documentaries and cartoons with frame interpolation, but turn it off for feature films.

Frame interpolation is designed not only to combat strobe, but also to increase the dynamic resolution of LCD TVs (only modern Panasonic plasmas are capable of displaying 1080 lines of dynamic resolution with frame interpolation disabled).

So we come to why some TVs show a dynamic picture this way, while others show it differently. To make comparisons, you need to set the interpolation value to one position or turn it off completely (different manufacturers call this item differently). Only then can we talk about different displays of dynamics.

Modes

It seems to me that this is the most important point at the initial stage of choosing a TV.
I have often heard people say that models of the same class from different manufacturers show completely different pictures (for example, the Philips 5-series is much better than the Samsung 6-series, etc.). With a 99% probability this is an error and it's in the details. At this stage, almost everything depends on the selected mode. An incorrectly set mode can create the worst image on the best TV in the world. When choosing a TV, pay close attention to the modes - look through all the candidates, choose the ones you like the most. If something doesn’t suit you, set it to “Custom” mode and adjust the color and contrast settings.

This is where several other myths come from. For example, about the fact that Samsung displays “nuclear” colors. This is true for phones where setup and calibration is nearly impossible or difficult. On TVs, absolutely all parameters are customizable. From here we move smoothly to calibration.

Calibration

This point will be very short, since this is not my environment at all, but a few words are worth saying.
Absolutely everything in our world has permissions. especially in mass production. The parameters of each released TV differ from both the standard and its counterparts. The degree of color deviation from the standard is measured by the complex characteristic DeltaE (this was briefly mentioned in the first part in the “image characteristics” section). The greater the deviation from zero, the greater the color deviation from the standard. As a person who does a little photography, I can say that the standard the colors are very deep, bright and saturated, they do not need any processing. TV calibration is a process when a signal is sent to the input from a reference source, which is measured at the output by a colorimeter. Then the master configures the TV so (only top and pre-top models have full calibration capabilities models) so that it produces colors as close as possible to the standard. On average, it is possible to achieve values ​​of 2-3 Delta E, which is considered indistinguishable from the standard by the human eye.

Instead of a conclusion or brief theses

In a brief form I want to write everything that I wanted to convey for those who do not want to read the whole article: 1) Each technology has its own purpose.
Plasma - for home cinema, large diagonals, viewing in the dark. LCD for viewing in bright rooms, in country houses, when selecting small diagonals, when working with a computer, or if you see plasma flickering. 2) When choosing a TV, pay attention to the modes. They decide a lot. Look at the modes of all candidates for purchase, select the ones you like best, and look at them. Do not compare TVs based on the modes set by store clerks. 3) When choosing a diagonal, start from the task. If you are choosing a TV for a home theater and are not strapped for money, there is never too much diagonal. In this case, for 2.5 m and 1080 content, the ideal diagonal would be 65″. If you are choosing a TV for other purposes, you can, and sometimes need to, choose a smaller diagonal. Don't forget that those TVs that seem huge at first seem much smaller over time. 4) Frame interpolation is a slippery thing. While it helps create smooth movement, it won't be to everyone's taste. It is important to know that there is no universal way to achieve smooth movement of fast-moving objects. There are trade-offs and you have to choose what you want. 5) If you are buying a top-end TV for home theater, it may make sense to have it calibrated. This is especially important for some TVs. In particular for those that have a very large DeltaE deviation out of the box. For example, Samsung ES8000 (8007), Sony HX923. Since the article was much longer than I expected, much of what I wanted to say did not fit here. Let's leave this for the final 3rd part. If you're interested, I'll talk about the types of 3D, their practical differences, pitfalls (complexities and features that sellers don't talk about), sources for playing 2D, and most importantly, 3D content (there are huge difficulties with this), well and about your choice, of course.

Thank you for your attention to my thoughts.

Three prohibitions

1. Don't sleep with TV on . Glare from the screen disrupts the production of the hormone melatonin, which is synthesized only during sleep in complete darkness. A lack of melatonin not only threatens insomnia, but also disrupts metabolic processes in the body and increases the risk of cancer.
2. Don't eat in front of the TV . In front of a blue screen, we eat more, even if we are not hungry. The fact is that while watching movies and programs, the brain is busy processing information and may be late in catching the signal that you are already full. Therefore, those who are accustomed to combining meals with watching TV eat on average 500 calories more and eat about 20 minutes longer than those who eat in silence.
3. Don't turn on the TV at full volume . Excessively loud sounds can lead to hearing impairment and nervous system disorders.

Parents' misconceptions about the benefits of TV

The modern world of television is large, diverse and exciting. At first glance, he has a lot to offer. But, in fact, for harmonious development, children need something completely different.

Filling them only with knowledge from the screen, often fragmentary and not age-appropriate, is absolutely ineffective and harmful. A child learns, first of all, from an adult with whom he has contact and a trusting relationship.

Reading books, walking together, observing nature, creativity, participating in the daily life of the family - these are the things that truly develop and prepare for future life. And informational television programs should only complement the learning process.

Sometimes parents stimulate and encourage non-speaking children to watch TV “so that they can speak sooner.” But the child will speak faster if you communicate with him, look at toys together and talk about everything you see around him.

Funny pictures on TV that move, make sounds and speak do not motivate them to voice them. But when a child looks at pictures in a book or holds a simple toy in his hands, he has to “make” these characters sound - out loud or mentally. First, the child pronounces primitive sounds - “kva-kva”, “bi-bi”; later, when verbs appear in speech, the plots and “speech” of toys and pictures become more complex.

With TV, you don’t need to make any effort: cartoon characters actively communicate, tell stories and move independently. The baby can only passively watch. This does not encourage speaking on your own at all.

Impact on the child

Surely, every parent understands that TV is harmful to the baby’s developing body. According to psychologists, it is contraindicated for children's viewing. You need to understand that a child, even after watching a seemingly harmless cartoon, becomes overexcited and may experience stress. This can affect the occurrence of whims, the development of fears, aggression, and anxiety.

1. TV deprives a child of the opportunity to develop his thinking and make any efforts to achieve a goal.
2. There is an underdevelopment of such qualities as determination, willpower, leadership, and memory capacity decreases. This can even affect delayed mental and speech development.
3. Visual acuity decreases and myopia develops. This is especially true for children under eight years of age, since until this period the lens of the eye continues to form.
4. The functioning of the musculoskeletal system worsens, posture is disrupted, which leads to flat feet and scoliosis.

Possible reasons for development

Lack of interests and goals in life, loneliness can lead to the development of telemania.
Dependence on television is called telemania and it is considered a disease. This condition negatively affects a person’s mental and physical health. Addiction to television indicates that there are no interests, the individual does not have any goals, so she wastes her life in front of the screen.

The development of addiction is influenced by certain factors:

• a lot of free time;
• the desire to live in a fictional world, someone else's life;
• the desire to escape from reality, from one’s problems;
• lack of friends;
• low self-esteem.

More often than others, the following are influenced by this dependence:

• lonely people who have no friends, no people with whom they can spend their time;
• insecure individuals who lack the courage to realize themselves and develop;
• children who sit in front of a screen when their parents do not have enough time for them;
• elderly people who find themselves retired now have no choice but to sit in front of the TV.