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

  • Tutorial
Hello again, dear habracheloveki.

The first part aroused some interest, so it was decided to continue this topic.
I want to say special thanks to those who paid attention to the first part. I did not think that my modest article would cause such considerable interest.

We can continue. In the second part, I would like to share my thoughts on choosing a TV diagonal for various applications, choosing a 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 impact of various parameters of the TV on vision.

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


We need to recall such a thing as a chassis. Roughly speaking, this is all the electronics inside the TV. TVs on one chassis have the exact same video path. Televisions with the same chassis always 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 directly compared: the chassis has no characteristics by which to compare.
When only a few players in the market produce LCD matrices (these are Samsung, Sharp and LG), almost every TV manufacturer develops a chassis. Of the major players, only Sharp (oddly enough, producing the best matrices on the market and unable to develop the chassis), who buys the chassis from Philips, is not the only one involved. Basically, the chassis differs from series to series (the lower the series - the simpler the chassis), one model of the chassis can capture several series (then TVs of different series will be similar).
Interesting, let me say it, Philips created this incident this year - it built all TVs from the 6th to 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 the different types of processing beautiful marketing names “Perfect Pixel HD”, “Pixel Precise HD” and if earlier there were real differences in processing between these names, now all the differences have been erased. I understand why Philips left different names for one, in fact, processing - older TVs should feel superior. But this is not fair.

LCD, Plasma - what to choose?

If you have not read the first part of the article and do not know the main differences between different image display technologies, matrices and various types of LCD backlighting, I advise you to read it.

If you choose a TV, first you need to decide which technology to give preference to. And this is the hardest part. Sellers unanimously said that there was nothing besides the LCD, only plasma was advised on the "advanced" video forums. Everything turned out to be a little simpler - everything has its purpose and each technology is suitable for its task.

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

- You want to use the TV as a monitor (Internet, image processing)
As you know, the LCD practically does not have a memory effect when the image "freezes" on the screen, so it is ideal as a technology for monitors. Plasma has an afterimage effect. In addition, gradations on the plasma display occur with the help of dithering , therefore, everything is not visible near a clear grid of pixels. Plasma as a monitor is not good.

- You want a TV with a small diagonal.
Small diagonals are where the LCD reigns supreme. FullHD-plasma starts only with 42 ".

- Your eyes do not perceive plasma TV imaging technology
There are people (they are only a few percent) who are not suitable for plasma because they see flicker. If you see flicker, set the mode to 96 Hz, turn off all the light ("energy-saving" lamps also have their own frequency and it can interfere with the plasma), twist the settings if you are using a PC. Only then it will be possible to talk about "flickering."

- You like oversaturated colors
I do not belong to this category people, but there are such people.

What factors influence the choice in favor of Plasma
- You want to view mostly
Blu-ray HD content , BD rips are all about plasma. These are her best friends and she most fully reveals quality content.

- You often watch television with dim lights or in the dark.
If light is the main enemy of plasma, then darkness is its best friend. It is in the dark that the image unfolds in full force.

- You choose a TV for the home theater
Cinema - this is what they buy plasma for. It is she who creates the effect of the “volume” of the 2D image, has a deep black level, is famous for the lack of light, and has excellent contrast transitions.

- You need a big diagonal TV:
50 "-65" are precisely those diagonals in which it is worth choosing a plasma. The 65 "LCD TV for home theater is a very strange choice.

- You like natural colors:
I take a little photography and imagine what the reference colors are. They are not dull at all as you might think, but bright, rich and deep colors.

Diagonal selection:

It's time to choose the diagonal for the TV. The following factors influence the choice of this diagonal:
- The distance to the TV. Attention - only the distance, the size of the room does not affect the choice of the diagonal.
- Content resolution. It is absolutely clear that the higher the clarity of the content, the closer you can watch TV.
- Destination. If you choose a TV for a home theater - this is one diagonal, a TV to the cottage - another.
- The budget. If, as often happens, the budget is limited, it is not necessary to buy the recommended diagonal, you can buy less.

There is such an organization: THX George Lucas, she distributes certificates for the image and sets standards in the field of television. It is her recommendations that I propose to use (especially since these are recommendations not of one THX, but of many and many companies and experts. I

offer you a table of diagonals:

When I bought my first modern 42 "TV for viewing from 3 meters, this table would shock me, but not now. Now I realized that the diagonal has the ability to "dry out" (when at first the TV seems large). Please note that the table is relevant when choosing a TV for a home theater. If you are not such a "gourmet" and select If you are watching TV to enjoy watching programs in the evening, you can pay attention to the smaller diagonals.
When choosing the diagonal designated THX for 1080, the diagonal does not seem large, the eyes do not run around the screen and do not get tired at all.

There is one simple rule - there aren’t many diagonals. Choose a TV for your home theater and are not limited in budget - take the diagonal from the table.

What about the eyes?

So we got to the most common myth that has remained in our memory since the time of the CRT. This is due to the radiation created by this type of television. Modern TVs lack this.
The myth says that the larger the diagonal of the TV, the more harmful it is for the eyes in the end.
The “breakdown” muscle , which is responsible for focusing, “breaks” . She stretches the lens so that the rays converge at the desired point. When the functions of the accommodating muscle are violated, a spasm of accommodation sets in and it becomes increasingly difficult for the eye to focus on distant objects. School children have a high probability of myopia.
What causes vision to “spoil” when watching TV? In general, because of the same reason that it spoils when reading a book, especially in dim light - the eye focuses at the same distance, strains, and the ability of the accommodating muscle is impaired. The muscle tenses the more, the closer and the smaller the object on which you want to focus.

What conclusions can be drawn from this?
- The closer the distance to the TV, the more your eyes get tired 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, it is exponential or close to it, and there is not much difference between 2 and 3 meters.
- The smaller the object on which you want to focus, the more your eyes get tired and the greater the likelihood of disturbance of accommodation functions.
That is, in theory, a small diagonal is more harmful than a large one. I was not able to find research on this subject, but with confidence we can say that, ceteris paribus, a large diagonal of an LCD or a plasma TV is no worse than a small one.

Frame interpolation

Many users ask why on some televisions fast movement of objects or panning looks smooth, but not on others. It’s worth starting with the fact that the standard 24 frames per second 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" image is called a strobe.
An absolute fact - 24 fps is not enough to transmit fast-moving objects or panoramic camera movement.
This means that when you turn off the software processing, without exception, all TVs will display this type of movement is not the best images. We are hostages of the standard.
There are several real solutions to this problem, but they all come down to an increased frame rate.
1) Frame interpolation. The fact that all modern TVs from an average price category are able to varying degrees of success. The TV on the fly analyzes 2 adjacent frames and draws another one or even 2 at its discretion.
2) HFR (high frame rate). Shooting initially in a higher frame format. It eliminates image processing artifacts from the TV processor, but requires special shooting, and most importantly - the carrier. The first and only film made with the HFR - The Hobbit: An Unexpected Journey . It’s not yet clear to me on what media it will be distributed and whether it will be distributed in the HFR at all.

All methods of increasing the frame rate carry one serious drawback - the loss of "cinema" image. The film looks unnatural, unusual. While the cinema world is at a crossroads - shoot and watch in HFR or at the usual frame rate. Which way will be chosen - no one knows.
Personally, I watch documentaries and cartoons with personnel interpolation, but turn it off for feature films.

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

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


It seems to me that this is the most important point at the initial stage of choosing a TV. I often heard words that models of the same class from different manufacturers show a completely different picture (like the Philips 5th series is much better than Samsung's 6th series, etc.). With a probability of 99%, this is a mistake and the matter is in the details.
At this stage, almost everything depends on the set mode. If you set the wrong mode, you can make the worst picture on the best TV in the world.

When choosing a TV, be careful about the modes - on all candidates, review everything, choose the ones that you like the most. If something does not suit you, set the "User" mode and twist the color and contrast settings.

From here come a few other myths. For example, about the fact that Samsung show "nuclear" colors. This is true for phones where tuning or calibration is almost impossible or difficult. On TVs, absolutely all parameters are configurable. From here we smoothly proceed to calibration.


This paragraph will be very short, since this is not at all my environment, but a few words are worth saying. Absolutely everything in our world has tolerances. especially in mass production. The parameters of each released TV differs both from the standard and from its brothers. The degree of color deviation from the reference is measured by the DeltaE complex characteristic (this was mentioned in passing in the first part in the “image characteristics” section. The greater the deviation from zero, the greater the deviation of the color from the reference. As a person who does a little work on the photo, I can say that the colors are very deep, bright and saturated, they do not need any processing.

Calibration of the TV is a process when a signal is applied to the input from a reference source, which is measured at the output by a colorimeter. Then the master sets up the TV so (only top-end and pre-top models have full calibration capabilities) so that it produces colors that are as close to the standard as possible. 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 abstract

In short form I want to write everything that I wanted to convey to those who do not want to read the whole article:
1) Each technology has its own purpose. Plasma - for home theater, large diagonals, viewing in the dark. LCD for viewing in bright rooms, in cottages, when choosing small diagonals, when working with a computer or if you see a plasma flicker.
2) When choosing a TV, pay attention to the modes. They decide a lot. Look at the modes of all candidates for a purchase, select the ones you like most, look at them. Do not compare TVs according to the modes set by sellers in the store.
3) Choosing a diagonal, start from the task. If you choose a TV for a home theater and are not constrained by the means - there are not many diagonals. In this case, for 2.5 m and 1080 content, the ideal diagonal will be 65 ". If you choose a TV for other purposes, you can, and sometimes need, choose a smaller diagonal. Do not forget that those TVs that at first seem huge after time seem so much less.
4) Personnel interpoltsiya -. slippery thing Although it helps to create a smooth movement, not all it will have to taste to know that universal way to achieve smooth motion of fast-moving objects there are no compromises and you need to choose what you.. want to.
5) If you buy a top-end TV for a home theater, it may make sense to calibrate it. For some TVs, this is especially important. In particular, for those that out of the box have a very large DeltaE deviation. For example, Samsung ES8000 (8007), Sony HX923.

Since the article came out much more than I expected, much of what I wanted to say did not fit here. Let us leave this for the final 3rd part. If you are interested, I’ll talk about 3D types, their practical differences, pitfalls (difficulties and features that sellers don’t talk about), about 2D playback sources, 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.

Also popular now: