4k resolution flat panel televisions, such as the LG 84LM9600 84″ LED LCD, are now available and potential buyers are wondering if the extra resolution is worth it. In some cases it is, but in most, it’s not. The details below can help you decide.
What Exactly is 4K (and 8K) Resolution?
The previous specification for HDTVs is based on the 1080p standard, which has a resolution of 1920×1080 (2.1 million) pixels. The UHD resolutions are based on multiples of this resolution with the same 16:9 (1.78:1) width-to-height ratio.
4k resolution doubles the number of horizontal and vertical pixels (versus 1080p HD), giving approximately 4 thousand (4k) vertical lines. More specifically, the resolution is 3840×2160 (8.3 million) pixels. In traditional terms, 4k could be called 2160p. This standard is also know as QFHD (Quad Full High Definition, or 4x the resolution of HD 1080p.)
8k resolution give four times the number of horizontal and vertical pixels vs. 1080p HD. This gives approximately 8 thousand (8k) vertical lines. More specifically, the resolution is 7680×4320 (33.2 million) pixels. In traditional terms, 8k could be called 4360p. 8k offers 16 times the resolution of 1080p HD.
The ITU and the Consumer Electronics Association have officially dubbed 4k and 8k resolution as Ultra High-Definition (or Ultra HD, or UHD, or UHDTV, or Super Hi-Vision.) This UHD name technically applies to both 4k and 8k, regardless of which of these resolutions it is. However, most manufacturers are clarifying the UHD nomenclature by specifying 4k UHD and 8k UHD.
Digital Cinema 4k has a resolution of 4096 x 2160 due to a slightly wider aspect ratio of 1.90:1. This aspect ratio would not be found in typical consumer products.
Will I be Able to Notice the Additional Resolution?
To be able to detect the additional resolution of 4k (or 8k), the screen must be large enough and you must sit close enough. So how do you know if your particular setup would benefit? Here’s your answer.
Based on the resolving ability of the human eye (with 20/20 vision it is possible to resolve 1/60th of a degree of an arc), it is possible to estimate when 4k resolution will become apparent for the average eyeball. Using the Home Theater Calculator spreadsheet as a base, I created a chart showing, for any given screen size, how close you need to sit to be able to detect some or all of the benefits of a higher resolution screen. (Click the picture below for a larger version.)
(For those of you not used to reading charts: screen size is on the horizontal axis; find your screen size and go straight up until you hit the 4k line. Follow it to the left. That is your minimum seating distance to fully benefit from 4k resolution.)
What the chart shows is that, for a 84-inch screen, 4k resolution isn’t fully apparent until you are at least 5.5 feet or closer to the screen. For a “tiny” 55-inch screen, you’ll need to be 3.5 feet or closer. Needless to say, most consumers aren’t going to sit close enough to see any of extra resolution 4k offers, much less 8k.
1080p 3-D Content on Passive (polarized) Screens
There may still be one benefit these screens can offer and it’s when watching 3-D Blu-ray movies. There are two types of 3-D glasses: more expensive Active Shutter glasses and lower-cost Passive Polarized Lens glasses. Active Shutter glasses deliver the full screen resolution to each eye; Polarized Glasses deliver only half the screen resolution to each eye (540 instead of 1080 vertical lines)
4k allows all 1080 lines to be visible when using Passive Polarized glasses, so long as you are sitting close enough to view 1080p (see chart above.) You wouldn’t be able to get the full benefit from 4k 3-D, but 4k content doesn’t really exist anyway.
What about 4k and 8k Content?
If you are among the rare few who has a giant screen and sits close enough to it to benefit from 4k resolution, will you still see much benefit? The answer is still “Probably not.” Regardless of screen resolution, the source material needs to have the same resolution as the display to see any real advantage. Video Processors will upscale any input to 4k resolution, but upscaling only offers a marginal improvement. Until true 4k and 8k content is widely available, which is a long way off, you are better off saving your cash and getting a 1080p HD TV instead.
As of this writing, the only readily available content source for 4k is the Sony PlayStation 3, and it can only display static pictures (not moving video) using the HDMI connection. This may be worthwhile for photographers, but probably not for anyone else.
In conclusion
The benefits of 4k and 8k are marginal at best. You have to sit unrealistically close to see the full detail and you also need 4k and 8k source material, which is virtually non-existent. If you want a 3D TV that uses Passive Polarized Glasses, you will be able to view 1080p content at full resolution. If you want to use a PS3 to view 4k photos, you could benefit from 4k. And if you use it as a computer monitor to view high resolution source material, you could benefit. Other than that, save your cash and purchase 1080p instead.
ISF states the the most important aspects of picture quality are (in order): 1) contrast ratio, 2) color saturation, 3) color accuracy, 4) resolution. Resolution is 4th on the list, so look at other factors first. Also, be sure to calibrate your display! I recommend the following for calibration.
Recommended Calibration Tools
- DVD: Digital Video Essentials
- Blu-ray: Spears & Munsil High-Def Benchmark Disc (my favorite)
- Blu-ray: Digital Video Essentials: HD Basics (most popular)
- Automatic Calibrator: Datacolor Spyder 3
“Just tell me what resolution HD TV to get”
If you don’t like reading charts and are looking for a quick answer, enter you screen size below to see how close you’ll need to sit to fully appreciate various screen resolutions.
[...] Does 4K Resolution Matter? | CarltonBale.com. [...]
What you are talking about is the micro effect. We should also look at the macro or the effect as a whole. The bottom line is that 4k makes things look a lot more “lifelike”…just look at one yourself side by side and decide. Sales people used to tell us the same thing for 720p on a 32″. which is a bunch of bs!
This sounds a lot like the video equivalent to the audiophile BS that I’ve been dealing with for years.
You want to claim that there’s some “macro” effect that makes it look more “lifelike”? Then do the hard work of proving you can see it in double-blind test. Same thing for 1080P vs. 720P on a 32″ screen.
And don’t tire me with snooty, self-promoting crap about how you’re an astute viewer with hawk-like vision and the finest source components that money can buy. Similarly, don’t waste my time with deprecating remarks about how I must somehow be inferior, or have inferior equipment to yours, if I don’t immediately agree with your proclamations about “lifelike” video “macro” effects.
You are absolutely right. On my first copy of Stereophile, 20 years ago, I cancelled my subsciption because of the endless and nonsensical articles about “bolting down” record and cd players to extract better sound through less vibrations and getting separate amps per speaker and gold plating everything … etc. The HDTV market must be reaching a sales plateau and that’s why they are pushing this ultra HD “snake oil” onto us.
[...] Referenced from this article by Carlton Bale [...]
[...] Using a screen calculator estimating a 50 foot screen (600 inches), I would have to sit a maximum of 37 feet away (American [...]
” … feet or closer for full benefit” is wrong.
” … feet or remoter for full benefit” is right.
No, what is written in the article is correct. For example, if what you stated were true, you could stand 1,000 feet away from a 42-inch display and see the full detail of 4k. Obviously, this is not possible.
Depending on ones visual acuity one has the be a specific distance from the screen moving(much) closer will not make the image sharper or more cohesive, there is a +/- distance that needs to be taken into consideration.
X number of pixels(image data) per degree, moving closer reduces the number of pixels per degree, thus making the image less sharp and reducing image quality. We need specific about that distance. Greater or closer to a point say x % no more or less.
Saying “or closer” gives the impression one can be right up to the screen and still get the benefit of 1080/2160, which is incorrect and misleading.
Hi Carlton – I want to thank you for this article – It has been very very helpful in shaping my understanding of the relationship between pixels and viewing distance.
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[...] nhất (ví dụ 4K là vạch tím, 1080 là vạch đỏ …) hay tính toán ở đây : CarltonBale.com – Còn khi ta coi phim giải trí, thì có thể ngồi lùi ra xa một ít, miễn đừng [...]
[...] The new Ultra High Definition is beneficial in theaters…. Check out carltonBale.com TV sizes, resolution and viewing distance. [...]
4k and 8k are completely pointless for the home. This is probably yet another money grab by the psycho dogs who rip babies of their candies in their sleep. The corporate whore bags of america. You’re telling us that a resolution that is used in the fucken movie theater where the image is blown up 100x is good for the home where the average screen size is 40″ or so. Suck a tail pipe already.
[...] 60 ppd Chart by Carlton Bale [...]
I don’t have the greatest vision, but I can easily see individual pixels on my 63″ screen from 10′.
The whole point is you want the pixels so small you CAN’T see them… You are measuring the other way around.
Furthermore — take a look at a good ‘hd’ tablet (one that fits into your “fully benefited” pixels-per-arc-minute calculation) and then look at a 1600×2560 Nexus (which is considerably higher resolution than you say we can benefit from). The Nexus looks considerably sharper.
Great site! What formula is used to find the min distance you need to sit from the screen to enjoy the effects of 4K, i.e. not seeing jaggies? Thanks
[...] (Credit: Carlton Bale) [...]
[...] (Credit: Carlton Bale) [...]
[...] (Credit: Carlton Bale) [...]
[...] (Credit: Carlton Bale) [...]
[...] this debate before when HD was coming to the market and the question was between 720p and 1080p (I always refer to this article Carlton Bale), our eyes simply cannot tell the difference between 1080 and 4K at comfortable viewing [...]
[...] can find various mathematical solutions to this problem, but here's one that's typical and also clearly written. Its conclusion: You'd need an 84-inch screen and you'd [...]
[...] input your vision number). Here are a few online calculators to check out: Reference Home Theater, CarltonBale.com, and Home Theater [...]
[...] your vision number). Here are a few online calculators to check out: Reference Home Theater, CarltonBale.com, and Home Theater [...]
[...] Bale, a tech writer, has written an excellent synopsis of what 4K means for the home viewer. Looking at the offerings that Best Buy Co., Inc. (NYSE:BBY) currently has, [...]