The 4K resolution is a standard originally used in the film (4K DCI) and is characterized by providing greater definition and image sharpness.
4K gets its name from its horizontal resolution, approximately 4,000 pixels, contrary to what happened with the 1080p and 720p standards that were named for their vertical resolution.
A little history about 4k
If we look back a few years, in the world of cinema there were two standards for the size of films, the 16mm, and the 32mm. However, with the arrival and improvement of digital equipment, film production and post-production began to be carried out on digital media. This caused the equivalent of these two formats or film widths had to be calculated.
These equivalents have been 2048 or 2K resolution for 16mm and 4096 or 4K for 32mm. After a while, specifically in 2013, it was RTVE who carried out the first 4K experimental test. A montage lasting about 5 minutes about the city of Barcelona and which was shown at the Mobile World Congress that same year.
However, it is a little later when the Corporation itself, together with Juan Carlos Gonzales and José G. Morillas, produces the first European commercial documentary in 4K. We refer to La Pasión del Prado, written and directed by the two creatives and which premiered at the San Sebastian Festival in 2013, although it was not broadcast on television until May 2017.
In that same year, 2013, the private company also carried out a satellite broadcast in 4K UHD resolution. It was Canal + through its new channel dedicated especially to this resolution and called Canal + 4K.
Between 2014 and 2017, RTVE also launched an experimental 4K channel called RTVE 4K through the Hispasat satellite, while Atresmedia broadcast the Champions League final in 4K technology. The 2018 World Cup in Russia was also broadcast in 4K through DirecTV for all subscribers that yes, who had UHD televisions and through the hiring of 4K decoders.
Today, there are many TV models capable of playing content in this resolution and there are more and more compatible devices and content available in 4K, especially on streaming platforms.
4K Technical Features
The resolution of the 4K DCI is 4096 x 2160 pixels (17: 9 aspect ratio) with a rate of 24 frames per second and a color depth of 8 bits.
This standard has been modified for use in radio and television, doubling the full HD resolution by reducing the vertical lines to 3860 while retaining the 16: 9 size of today's displays.
Therefore we have:
- 4K DCI (cinema) = 4096 x 2160 = 24 FTS = 8 bit color
- 4K UHD (broadcast and tv) = 3860 x 2160 = 50-60 FTS = 10-12 bit color
4K and HDR: better resolution, brightness, and color
HDR has improved picture quality dramatically and is currently only implemented on 4K televisions. The high-end ones have 10-bit panels instead of traditional 8-bit ones, which means that they can reproduce 1 billion colors instead of the 16.7 million that 8-bit screens reproduce. In turn, the luminosity of these panels is higher, which makes the image much more realistic.
Of course, you have to differentiate between two types of televisions with HDR: those that carry it and those that don't. Most cheap 4K televisions will state that they have HDR, but in reality, we are dealing with "compatibility" with HDR content. In other words, they are capable of reproducing content in HDR, but what they show you are not, but they make approximations of those extra colors towards those that they can reproduce.
Therefore, if you want a TV to have real HDR, what you have to do is make sure that it complies with any of the HDR standards, such as Dolby Vision, HDR10, or HDR10 +. All televisions that can reproduce true HDR are HDR10 compliant and thus obtain certification from the responsible association. If you put HDR10 on, you almost certainly have real HDR.
Will 4K reach DTT?
It has been five years since 4K TVs with HEVC were released. However, in all that time, although the content has improved on the Internet and IPTV, in DTT we still have 1080i at most because the spectrum is very small since the codec used is H.264 with MPEG4. In the case of wanting to broadcast in 4K, you could, since using HEVC you can use the same spectrum and offer more quality.
The problem is that the majority of the population does not have decoders compatible with that codec, being only those sold since 2017 with DVB-T2. All televisions that are sold already have to be DVB-T2 if they have more than 32 inches, and in a few years all the DTT channels will be all Full HD, and we may even see some in 4K. TVE has already carried out successful broadcast tests, so in the future, we will see them for sure. In the operators' televisions, there is no spectrum limit for broadcasting over the Internet, so that there is no problem to broadcast those channels, in addition to having a higher quality.
4K gaming
Playing in 4K has been possible on PC for years. All you need is a powerful computer, and even with a mid-range one, you can play undemanding games. Consoles like PS4 Pro and Xbox One X also have a multitude of 4K titles, although many of them use techniques such as checkerboarding to resize titles with resolutions such as 1440p or 1600p.
To play games, make sure you have a graphics card with HDMI 2.0 or DisplayPort 1.2. In addition to a TV, there are cheap 4K monitors like the U28E590D, with 4K resolution, 60 Hz, and 1 ms response time for 244 euros. Although it is a TN panel, it will offer us a great user experience and is ideal for playing if you are not interested in 144 Hz.
If you are interested in 4K and 144 Hz, there are already monitors with that resolution and refresh rate, but you will have to save a lot because they are still worth more than 2,000 euros.
4K TV Models and Technologies
There are currently two types of technologies for 4K TVs: LCD and OLED. LCDs are the ones that have been around the longest, and consist of an LED panel that backlights an LCD panel from behind, and it is the LCD panel that, through modifications to the liquid crystal on the front, lets through a certain amount of light. A bypass of these panels is Samsung's QLEDs, which instead of using white light for backlighting, use blue light and quantum dots to enhance the amount of light that passes through and the color.
In the case of OLEDs, it is the individual pixels themselves that light up, generating a more contrasting and realistic image. However, its organic components wear out over time, so be careful not to leave items fixed on the screen for a long time. Although the brightness of these panels is lower, the effect is comparable to that of the best LCDs due to better contrast, which is described as the difference between the panel's darkest and brightest points. An OLED panel can turn off its pixels and make black pure black, such that the contrast ratio is infinite.
Currently, the best LCD TVs are undoubtedly QLEDs from Samsung, which has licensed Quantum Dot technology to other manufacturers. Samsung's are the brightest and best colored, with a wide variety of models to choose from. Among some recommended models we have the Q60 range with 1,000 nits of brightness, with the 55Q60R for 817.49 euros.
For its part, LG is the only manufacturer of OLED panels, and its televisions are the best that use this technology. There is a wide variety of ranges, but the lowest range of OLED exceeds 1,000 euros because it is a technology that already offers excellent performance at the most affordable price. The C9 range launched this year is the best they have to offer.
In the future, there will be new technologies that will improve image quality, such as the QD-OLEDs in which Samsung works, which will not need backlighting like the QLEDs and will have pure blacks with the advantage that the pixels will not wear out. as in OLED.
Is the leap to 4K worth it?
Sure, if you have a pre-2015 Full HD TV then it's worth switching to a 4K TV. It's not just the higher resolution that makes it worthwhile to upgrade; there are several other advantages to purchasing a 4K TV. We have the Internet to see streaming content of higher quality and resolution, mobile access, connectivity with the future standard DVB-T2, HDR, DTS, and Dolby sound, the ability to capture television and replay it later, a plethora of applications for movies and series, a player with DLNA built-in, increased energy efficiency, and so on.
In addition, all this you can get for just 400 euros, or 500 if we go up to 55 inches, which is what the cheapest 4K televisions are worth. Without a doubt, if you are thinking of changing your television, right now is an ideal time to do so.
The jump to 4K may be the last "necessary" jump for television since between 4K and 8K there is hardly any difference in quality from a certain distance. Nobody watches TV within a meter, which is where the difference is noticeable with 8K in 55 inches. Therefore, it will be very difficult to try to sell these new televisions due to the level of sophistication and high quality that 4K has. They would have to make technologies such as microLED exclusive to 8K for it to be worth the leap.