What is 4K Resolution?
Ultra HD Resolution Explained
4K Ultra HD TVs are here, but is 4K a technology breakthrough, or...
The highest display resolution is no longer 1080p with its 1920 pixels by 1080 lines; instead, 2012 has brought the first of a new breed of high definition display - 4K TVs, supporting four times the picture detail afforded by the 1080p HDTV standard. 2013 followed suit with more 4K TVs then we ever expected from both large and small TV makers at all TV screen sizes.
But what is 4K? What are the implications of this new technology, and what does it mean to have four times the picture detail over the typical TV size found in home entertainment? Would moving from 1080p to 4K resolution deliver the same 'WOW' factor we experienced when moving from standard to 1080p HDTV?
And taking into account the expensive price tag of 4K hardware, are 4K video projectors and 4K TVs worth considering for home entertainment? Equally important, what about native 4K content to watch on your new 4K TV?
We discuss this and more in this TV guide; you can join our discussion at the end of this page.
LG 84LM9600 - LG's 4K resolution 84-inch TV
as exhibited during CES 2012; this 84-inch Ultra HD TV was the first 4K TV to hit the market in November 2012. 4K is made for huge screens, yet this is still one of the few 84-inch 4K TVs presently available.
Ultra High Definition TV Technology
Up to CES 2011, 1080p HDTV was the highest available display resolution for the home market. However, with CES 2012, this was no longer the case; the new highest resolution standard available today for end customers is 4K. Mind you, it was not before November 2012 that the first 4K TV hit the consumer market; this was the LG LM9600, soon to be followed by Sony X900 4K TV.
With 2013, the number of 4K TVs increased, and apart from Sony and LG, it is now possible to find 4K TVs from a number of small and large TV makers, including Samsung and Seiki Digital; we should also expect 4K TVs from Panasonic later during the year. Present pricing range from typically $5,500 for a 55" TV such as the Samsung UN55F9000, to around $7,000 for a 65" set such as the Sony XBR 65X900A.
Despite what the TV industry is saying, 4K resolution represents more of an improvement over existing display technology than a real breakthrough in TV display technology.
What is 4K?
More than a standard by itself, 4K is an umbrella term adopted by the industry in 2012 to refer to technologies capable of delivering an image that is around 4,000 pixels wide by 2,000 pixels high; that is approximately four times the resolution supported by 1080p HDTV, or twenty-two times the resolution supported by DVD-video and enhanced digital TV.
Digital Cinema Projectors based on the Digital Cinema Initiative (DCI) system specifications support both 4K and 2K resolutions. The Digital Cinema System specifications also specify two different 4K resolutions, 4,096 x 1,714 pixels for an aspect ratio of 2.39:1 and 3,996 x 2,160 pixels for an aspect ratio of 1.85:1. Instead, Sony Pictures uses its own 4K resolution based on 4,096 pixels by 2,190 pixels while Academy 4K is a 3,656 x 2604 pixel standard with a 1.37:1 aspect ratio. On the other hand, Full Aperture 4K is another cinema standard that though labeled as 4K, supports a larger number of pixels thanks to its 4,096 x 3,112 pixels image.
In the home, things are a little bit simpler. All we have are the two recently added 4K resolutions to the latest HDMI 1.4 specifications, namely 4K/2K supporting 4,096 x 2,160 pixels resolution and Quad HD with its 3,840 x 2,160 pixels; the latter resolution has now been labeled by the Consumer Electronics Association (CEA) as Ultra HD, and is the only 4K resolution that has the same 16:9 aspect ratio as present 720p and 1080p HDTV.
Mind you, the Consumer Electronics Associations (CEA) does not specify some exact resolution. Rather, the CEA requirement here specifies a minimum 4K resolution, saying that TVs carrying the Ultra HD TV label should support at least 3,840 horizontal pixels and 2,160 vertical pixels, this apart from having at least one input connector capable of native 4K Ultra HD signal connectivity. The latter requirement is very important as the first 1080p HDTVs to appear on the market a few years ago did not support 1080p connectivity despite having a 1080p resolution display!
In the beginning... some background history
As you may have expected, it all started in the movie theater! Digital cinema represented the ideal way ahead to replace film stock; the latter is not only very expensive to produce but also expensive to transport and store.
However, when George Lucas started experimenting with digital cinema in the late 90s, it soon became clear 1080p does not support a high enough resolution for the giant screens of the movie theater. With 1080p, the result is either a too soft an image or one where it is possible to see the pixel build-up structure of the image, this depending on the projection technology in use. Both image softness and a visible pixel structure are extremely annoying image quality artifacts that should be avoided especially on the giant screens of movie theaters.
The movie industry needed a higher resolution standard that is more suitable for the large screen. And here comes DCI. It was in 2002 that the Digital Cinema Initiatives (DCI) was set up with the scope of setting up a suitable digital standard. The first DCI standard was released in 2005 specifying both 2K and 4K resolutions.
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In-home 4K Resolution TVs
Sony 84-inch XBR-84X900 4K TV - a $25,000 piece of gear that uses the same 84-inch panel made by LG for the LM9600!
For the expensive price, you get big detachable 50W speakers, a detachable solid chrome stand, and yes... a Dell PC that acts as a server loaded with 10 full-length 4K movies (plus a bunch of shorter 4K content), to make up for the present almost non-existent native 4K content.
As we have seen, 4K resolution in the cinema was not born in 2012; yet in the home, 4K TVs represent the latest emerging high definition technology, which the TV industry is trying to push on the consumer market. All major TV makers presented 4K TV prototypes during CES 2012, and more 4K TVs were seen during CES 2013. Yet only a few major TV makers have so far released 4K TVs.
These include the Sony - which apart from the super expensive 84-inch XBR-84X900 (featured here), have two smaller sets within their X900A series - the 55-inch XBR 55X900A and the 65-inch XBR 65X900A 4K UHD 120Hz 3D LED TVs; the latter is one of the best-selling 4K TVs despite a price of $7,000.
Other similar models at these screen sizes are available from Samsung, LG, and Toshiba. These are the LG 55" 55LA9700 and the 65" 65LA9700 Ultra HD TVs with Smart TV, the Samsung 55" UN55F9000 and 65" UN65F9000 Ultra HD TVs (featured on the right), and the Toshiba 58" 58L9300U and 65" 65L9300U 4K TVs.
These are all 4K LED TVs with Smart TVs with the main difference being that like the Sony, the Samsung 4K TVs use a 120Hz refresh rate, while the LG and Toshiba models are 240Hz 4K TVs. These 4K TVs are selling within the same price bracket as the Sony X900A equivalents. In the meantime, Panasonic is expected to release its 4K TVs later during the year.
Out of the major TV makers, it is Sony the TV manufacturer that seems to be investing more in 4K, not only with the launch of the first 4K video projector (the VPL-VW1000ES), and also 4K TVs, but also with a planned 4K movie service to feed the latest breed of 4K Ultra HD TVs.
These movies are expected to exceed 100GB in size though the industry is looking on new more effective compression formats to reduce this size.
Expect 4K TVs to be large, but...
Though for technical reasons, we would have expected 4K TVs to be large, so far, there are only three 84-inch 4K TVs available on the market; these are the LG and Sony models already referred to earlier on in this article, and the Toshiba 84L9300U. The LG and the Toshiba sets are selling at $16K and $17 respectively while the Sony is selling online for anything between $25K and $35K! Despite this price difference, the Sony and the LG are making use of the same display panel made by LG! The only real thing you get extra with the Sony for the higher price tag is the server loaded with 4K content.
Instead, 4K TVs are becoming mostly available at the 55-inch and 65-inch screen sizes. We find this strange as at 55-inch and less, 4K resolution is in most applications a definite waste; the only justifiable use of 4K at the smaller screen sizes is in professional photo and video editing applications (where you have to sit just a few feet away from the screen).
Some TV makers like the relatively unknown Seiki Digital have also put on the market cheap 4K TVs at even smaller screen sizes; these include the Seiki Digital SE UY04 4K HD TVs which are available at 50-inch and 39-inch for $1,115 and $699 respectively. These are definitely cheap prices for 4K TVs - it is no wonder these are proving to be popular in TV sales; yet one has to keep in mind that here we are dealing with nothing more than no-frills entry-level LED TVs with 4K resolution, and this at screen sizes where it would be impossible to perceive the picture detail advantage resulting from the higher pixel count. In any case, if you want a cheap 4K TV, there you have it!
And extremely expensive...
84-inch sets are selling at exorbitant prices, while the Sony's 4K native resolution 3D home theater projector, the Sony VPL-VW1000ES, is presently selling at amazon for $25,000!
But even smaller 65-inch and 55-inch 4K TVs are significantly expensive in comparison to similar featured 1080p HDTVs, with a price difference that is at least three to four times that of an equivalent 1080p HDTV. Worst still, do not expect some superior picture quality other than the added picture detail of 4K resolution; most of the available 55-inch and 65-inch 4K TVs are noting more than mid-range TVs, with most premium 1080p LED and plasma HDTV sets doing much better in terms of picture quality.
Our simple straightforward answer is NO! And this for a number of reasons apart from the expensive price.
4K is made for the BIG screen
To enjoy the benefits of 4K technology, you need a very big screen, a screen size that generally goes well beyond the average TV size you expect to find in a typical home entertainment setup. And even with a very big screen, do not expect that shifting from 1080p to 4K resolution will bring about the same 'WOW' factor you experience when moving from standard definition video to HDTV - at least not with 2D content. Why?
The typical 'large' TV screen size in home entertainment is 55 to 65-inch. Yet, using 4K resolution on a 55-inch or even a 65-inch HDTV is like trying to enjoy the benefit associated with the higher resolution afforded by 1080p HDTV over 720p resolution, on a small 32-inch screen! You simply would not be able to enjoy the improved picture detail.
At above 75-inch, you may just start enjoying the benefits of 4K resolution technology over 1080p, however only 'just' and only if you watch your TV from too close a viewing distance. In reality, you need to move to a larger screen size — 80" and above — to start enjoying the benefits of 4K resolution.
Nevertheless, what is a too close viewing distance for 4K?
Many people sit at approximately 10 feet away from their TV irrespective of the screen size or display resolution. As we further explain in our TV viewing distance guide, a person with normal eyesight sitting at 10 feet away from an 80-inch screen will never be able to see the pixel build-up structure of a 1080p image due to visual acuity limitations.
This means that with an 80-inch screen, the benefits of 4K would only start kicking in if you were to sit significantly closer — maybe 8 feet away or less — from the screen. It is no wonder that in a recent 'hands on' review conducted by the Cnet editors on the Sony XBR84X900 at Sony's Manhattan headquarters, the Sony engineers set the seating position at 8ft away from the screen; and the Cnet editors added that they had to move to as close as 6 feet to start seeing any difference with 2D content between native 4K content and the same content compressed to 1080p on the same 4K TV.
Some may be fast to note that the Cnet comparison is flawed by the fact that the Sony 4K TV is in effect upscaling the compressed 1080p content back to 4K once again to display it on the TV, adding that the quality of this upscaling is very much dependent on the quality of the video processing.
This is all true, yet I doubt anyone would ever consider sitting closer than 10 feet away from such a massive screen. So why bother about 4K!
And you know what?
Even if you were to sit close to the screen to enjoy the added picture detail supported by 4K technology, there is still a high probability you would not be able to see all the image detail. The reason is that the smallest detail a person's vision system can see depends not just on the size of the detail itself; as further explained in our contrast ratio article, this also depends on the difference in brightness and contrast between adjacent picture elements. To complicate matters, the contrast sensitivity function of the eye is not linear. This explains why a bright enough lower resolution high contrast image may appear to have an apparent higher resolution than a higher resolution but lower contrast image.
The truth is that you need an even bigger screen — 100-inch and more — and sit at a closer distance than what many consider is a comfortable viewing distance, to start enjoying the benefits associated with the added picture detail afforded by 4K technology; this being especially so if what you are watching is 2D content!
In other words, a 4K Ultra HD TV in home entertainment is our opinion, a non-starter; rather, it is a foolish preposition by TV makers.
With 4K resolution projectors, well... if you can afford to enjoy giant projections in the home, then possibly yes; but keep in mind that at these massive projections, there arise other limitations with the most obvious being the brightness limitation of in-home projectors. Such high resolution also imposes more demanding requirements on the video processing, the projector lenses and even the projection screen, especially with the use of an acoustically transparent screen.
4K Resolution and 3D
The only justifiable application of 4K in the home at the 'smaller' 65-inch to 80-inch screen size is if you are making use of passive 3D-glasses technology, glassless-3D, or 3D DLP.
As explained in our 3D TV formats article, passive glasses 3D technologies deliver a 3D image that is at half the resolution supported by active glasses systems. This explains the slight 3D image softness some experience on large area 1080p displays arising out of the use of these 3D technologies in comparison to 1080p 2D content and 1080p 3D active glasses systems.
Using the higher resolution 4K display with passive 3D glasses technology would solve this image softness issue, as the resultant 3D image would have a picture resolution that in this case is still twice that of 1080 HDTV. In the case of the LG and Sony 4K TVs using passive 3D glasses technology, the 3D image would have a resolution of 3840x1080 pixels per eye.
One interesting feature that has emerged with 4K TVs is the two-player split screen feature as implemented on LG LA9700 series of 4K TVs (when playing compatible games). No more need to split the screen; through the use of special glasses, this feature makes it possible for each player to see his unique point-of-view in 2D and across the entire TV screen, without being able to see the opponent’s on the same TV screen.
Lack of 4K Content
It seems that with 4K resolution, the TV industry is once again making the same mistake it did with the release of the first 3D TVs in 2010. At that time, it pushed 3D-in-the-home when there was practically no 3D content available for viewers to enjoy the latest and greatest TV technology since color television.
Moreover, with 4K technology, the end consumer is once again being faced with the same lack of suitable content for this new technology. Sony is including a server with its 4K TV that comes loaded with ten full-length movies; Sony is also planning to introduce a 4K movie content delivery system later this year. But 4K would still remain practically non-existent in the immediate future.
In the absence of native 4K content, displays and disc players will have to upscale 1080p content to 4K resolution. But this is like watching converted 2D to 3D; it is not the same as true 3D. And upscaled 4K content is definitely not the same as content shoot in 4K resolution in the first place. It is true that the resultant image quality is very much dependent on the quality of the video processing; the latter can make or break the upscaled image, but upscaling generally adds a number of image artifacts that become more visible on the larger screens of 4K Ultra HD TVs.
A 3D Blu-ray disc player capable of excellent AV performance. Features include SACD/DVD-A playback, 4K upscaling, 2D-3D conversion, DLNA networking, and wireless Internet streaming.
However, even if you were to settle for upscaled 1080p content to obtain a 4K resolution image, do not expect to find many players with this capability.
We are only aware of just two players that come with 4K upscaling. These are the excellent OPPO BDP-103 universal disc player featured on the right - presently selling on amazon for under $500, and the slightly cheaper Sony BDP-S790 Blu-ray player.
An even bigger hurdle than the lack of 4K content itself is that at present the Blu-ray specifications do not support 4K resolution even thought the media itself has enough storage capacity for 4K content.
We expect that at some point in the near future, support for 4K resolution will be added to the Blu-ray specifications; in fact, it appears that Sony is already in discussions with the Blu-ray Disc Association to finalize 4K specifications for Blu-ray. This represents an essential step towards delivering in-home 4K content.
The TV manufacturing industry would have wanted 3D TVs to be the same big thing as LED TVs and Internet-connected HDTVs, yet sales of the first 3D TVs in 2010 were a total flop! Eventually, TV makers had to embed the 3D feature on a wider range of HDTVs — including entry-level sets — almost for free to push 3D into the home and entice consumers spend more on 3D-ready gear and 3D content.
With 4K resolution, the industry may once again be heading towards that same failure. It is delivering the hardware — and this at a very expensive price — yet there is still no generally available native 4K content to watch at home on 4K Ultra HD TVs and 4K-resolution video projectors.
Even if native 4K content were available, in-home 4K resolution would still lack the WOW factor the TV industry is trying to make you believe this technology can deliver. You would not be able to perceive the same level of improvement in picture detail over a 1080p display in a similar manner to what one enjoys when moving from standard to high definition.
Simply put it, 4K resolution is not for the average-size home TV; maybe for video projectors if you are after massive 3D 100-inch plus projections; but definitely it is not for your TV, even if that TV is a ridiculously expensive 84-inch set!
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