What is 4K UHD

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4K, UHD, HDR (High Dynamic Range), Wide Color Gamut, BT.2020 are some the words that are so familiar to the techies as they are unknown to the general and mostly casual consumers. Manufacturers like Samsung, LG and Sony along with all the big studios are always trying to push new technologies to the public in their try to remain relevant  and in the game as well as increase their profits by selling the best new thing to the hungry for new toys crowd.

But new tech needs to have the necessary promotion in order for the casual market to learn and adopt it. And as these new technologies and formats become mainstream a lot of people are asking what is 4K UHD and if they need to have a TV capable of displaying this new format.

A few years ago it was James Cameron’s Avatar that brought the 3D craziness upon us. And of course most technology manufacturers tried to profit from that by pushing 3D to the consumers and promoting it like never before. Unfortunately 3D although still popular among certain groups and mostly among projector fans it never really became mainstream and the main reason was that it required to wear glasses all the time that were becoming very tiresome for many people to use for a long time and no matter how you see it, it was not a very practical way to watch your favorite movie.

And not to forget that different manufacturers were using different types of 3D technologies making the glasses useless in case you would change your TV. Over the years the manufacturers tried to improve the technology  with various ways, we even saw some prototype 3D TVs that didn’t need any glasses but in the end manufacturers decided to abandon the effort altogether.

So they tried to find the next best thing. And this came in the shape of 4K UHD. Until now the best picture we could get was from Blu-ray discs as they were giving us a Full HD 1920 x 1080 resolution image. This was enough and still is adequate for many people. But as always technology is pushing things forward and Full HD is a thing of the past so there was a need to promote something new.

Pushing a new format to the public is not a difficult thing. What is difficult is to make enough consumers adopt it in order to reach critical mass so it can be considered mainstream. And when UHD disks and players arrived along with 4K TVs that were in the market for some time people started wondering more and more “What is 4K UHD?”.

4K UHD has a display resolution of 3840 x 2160 pixel offering much more picture detail than Full HD. But the increase in resolution was only one part of the new format had on offer. What really made the new format shine are HDR and Wide Color Gamut. The first one is a technology that offers much more in contrast and make colors more bright while the second can make TVs show a wider area of the color spectrum. In the picture below you can see a simulated comparison between an HDR image and a non HDR image. You can see how HDR is making the colors more vibrant and the difference between bright and dark colors are more pronounced.

What is 4K UHD

In a picture below you can see a comparison picture of the different Color Gamuts. Most of the Full HD TVs in the market support the Rec. 709 Color spectrum. All the new 4K HDR TVs must be able to show almost all the DCI-P3 color spectrum. As you can understand by this graphic the new 4K HDR can show much more colors than what was previously possible. This means much more accurate color representation and closer to the real thing. The goal for the future will be to have TVs that can show the full Rec. 2020 Color spectrum but we are far from this kind of technology yet and no TV from today can come close to that yet.

Now with all these new technologies the only sure thing was that it would mix the consumers and drive them away from this new format. That’s why the UHD Alliance was created consisting of all the big TV manufacturers in order to set the standard of what would later become the UHD Premium Certified stamp as a way to show to the consumers that a product meets the minimum requirements for all these new technologies.

So what does a UHD Premium Certified device must support?

  • A minimum resolution of 3840 X 2160 pixels also known as 4K
  • 10 bit color depth or above
  • A least 90% of the DCI-P3 color spectrum
  • BT.2020 color representation
  • Color Palette (Wide Color Gamut)
  • A combination of peak brightness and black level either:
    – More than 1000 nits peak brightness and less than 0.05 nits black level (For LCD TVs)
    – More than 540 nits peak brightness and less than 0.0005 nits black level (For OLED TVs)

What is 4K UHD

Now the above requirements are the absolute minimum a device must support to get the certification stamp. There are a lot of devices out there now that already exceed these requirements. On the other hand there are also a lot of devices that meet these requirements without having this stamp of approval. A great example of this is the VISIO TV manufacturer. So the best thing to do before buying a new device and you want to be sure it supports all the new features is to check the specifications rather than to look for the UHD Premium certification.

And to make things worse the are many so claimed 4K HDR TVs out there that cannot do justice to any HDR content as they may be able to support certain HDR technologies but don’t meet the minimum requirements set by the UHD Alliance and this results in many casual consumers getting TVs that in theory can display UHD but in reality are half baked solutions and cannot do real justice to the format.

If you are thinking to buy a home entertainment center one thing you need to be careful about is that you need all components in the chain to support the minimum features mentioned above. This means the TV, the AV receiver and the disc player which in this case is the UHD player. Here we should mention that one thing a lot of people forget is that except from these components a vital part of your home entertainment center in order to work as it should is to have the proper HDMI cables also. If the HDMI cables you are using are not supporting the latest protocol which is HDMI version 2.0b then you will not be able to make your system work correctly. You can read my article about HDMI cables HERE where we analyze all the HDMI protocols and give suggestions on what you should pay attention to when buying.

What is 4K UHD

Unfortunately in our experience with 4K UHD what we have seen is that in order to calibrate your system to be fully 4K UHD ready and have everything work as they should it needs you to dig deeper than what a casual user would and this means calibrating and fiddling with settings in all devices something that for us is a big minus for the new technology to become mainstream. With DVD and even Blu Ray you would connect everything together and most of the times it would work flawlessly without the need for any extra calibration or changing settings parameters.

We consider ourselves tech guys, people that most of the time don’t even read the manual of every new equipment we buy or test. But with 4K UHD even we struggled to make everything work flawlessly. We specifically remember one instance, when we started digging deeper into the new format, where we had setup everything perfect but when we were playing a UHD disk we were getting only 4K resolution but no HDR to the TV.

After a lot of search we found out that most 4K TVs that support HDR and Wide Color Gamut have an option that you have to enable for your HDMI input in order to get everything working correctly. In our case it was called HDMI True Color in the Samsung’s TV settings. Examples like these show that this technology while impressive is hard for the masses to use easily. Mainstream consumers shouldn’t need to search the internet to find out they need to enable an option on their TVs in order to get everything working.

What is 4K UHD

We see in a lot of forums the question “Is 4K worth it?”. As with every technology there are hits and misses and the same applies with this new technology. We have seen movies in 4K UHD that show completely spectacular and others that don’t justify the purchase of a new disc. It really depends on the studios to produce discs that really show off the capabilities of the 4K UHD format and this will really be the selling point of it going forward.

But the most difficult aspect of this 4K era is that instead of making things easier now it has become even worse as more new features and technologies have appeared. In the beginning it was only 4K and HDR but now it’s also HDR10+ vs Dolby Vision, we have new Filmmaker and HGiG modes, we have IMAX Enhanced equipment, Netflix calibrated modes and so many others technical names that for those being in the loop may sound familiar but there is a huge number of people that have no clue what all these mean. And if there is one thing that manufacturers really have to focus on is to give consumers an easier way to handle all these because not everyone is a tech savvy or keep paying attention to all the new technologies that come out every year.

So in order to summarize, yes the new format is worth it and there are movies in UHD that look far better than anything Blu-ray could ever achieve. As more devices are released to the market the prices will go down and 4K will become more affordable for the masses. If you are planning to get a new entertainment center there is no better time to do.

What is 4K UHD

I hope you enjoyed this article and if you want to share your experience setting up your new 4K home cinema, need any help setting up your new home entertainment center or you have problems deciding what you should buy or need any suggestions please feel free to leave your comment below.

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6 thoughts on “What is 4K UHD”

  1. Hi I was looking at this 4K symbol everywhere and I still don’t get it until I read your article!
    I never knew there was so much behind 4K as the only thing i knew was that it has something to do with the number of pixels on the screen but little did i know that there are colours, HDR and so many more inside!
    I also agree with you that the integration of 4K ‘ain’t there’ yet as it’s still a little troublesome to set up but once it’s set up and running, it’ll definitely be something worth admiring!

    • Every new technology in order to succeed and become mainstream needs to be easy to use it. And 4K is not there yet as there are too many parameters that need to setup to have everything working correctly. Hopefully companies will take notice and make things more simple for the masses.

  2. Hi Stratos, this is an amazing article. Just when I thought I know the basics of HD and 4K, I was in for the information ride. Super thanks for this. I remember when I watched my first blu ray video and how I was mesmerized by its crisp true-to-life images. Then a few years ago, I purchased my first HD TV and I was like a kid glued to the TV almost all day long on the first few days. Now, seeing the 4K UHD leaves me in awe. I guess it’s the constant pursuit of our creative psyche that makes us want to see moving images as real and as clear as possible. Soon, I’ll purchase a 4K TV for the family and I can imagine how my kids would grow up and thinking how we managed to live decades ago without it. Super thanks bro =)

    • Technology never stops to progress. I am sure in 20-30 years even 4K UHD will look as a cassette player looks today. This is progress. But the point is to enjoy every moment and the best thing right now is 4K UHD so i hope you get on the ride soon!

  3. Great article Stratos. I haven’t bought a TV or monitor in several years and I have behind on what all this new technology is about. I have been trying to get more up to speed but have been struggling without a lot of research. This article really cleared it up for me. As I prepare to purchase something towards the end of the year I will be back to make sure I am up to speed again.



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