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8K TV: What you need to know

After years of concept models, you'll finally be able to buy 8K TV this year. Should you care?

8K

Samsung's 85-inch Q900 will hit the US in October.

Sarah Tew/CNET

4K is dead, long live 8K! 

OK, not really. But the day will come when 4K goes the way of all those lower resolutions and is replaced by a bigger number, in this case 8K. The first 8K TV to arrive in the US will be the 85-inch Samsung Q900 this fall.

We've seen concept 8K TVs for years, but the Q900 is the first you can actually buy. It's not the first in the world, however -- that honor goes to the Sharp 70-inch LV-70X500E 8K monitor that started shipping earlier this year to Europe (for 11,000 euros) after going on sale in late 2017 in China, Japan and Taiwan. These TVs will almost certainly usher in more 8K sets in 2019 and beyond, like an 8K OLED TV from LG. Now that the age of 8K TVs is almost upon us, you might have some questions.

Does this mean 4K TV is already obsolete? Do you need to rush out an buy an 8K TV this year or risk being unable to watch your favorite shows? Should you throw your brand-new TV out the window in a fit of disgust at its appallingly low 4K resolution? 

The answer to all of these questions is "no." Here's why.

What is 8K?

A traditional HDTV from a few years ago is 1080p, which means it has 1,920 pixels horizontally, and 1,080 vertically. Many digital cinema projectors -- the ones in movie theaters -- have a resolution of 2,048x1,080. Because it's common in Hollywood-speak to only refer to the horizontal resolution, they call that "2K" but it's basically the same as the HDTV 1080p you have at home.

1080-4k-8k-comparison
Mathias Appel/HDMI Licensing

The term "4K" comes from the digital cinema side, too, with a horizontal resolution of 4,096, hence "4K." However, on the TV side, manufacturing efficiencies meant we got double the horizontal and vertical resolutions of 1080p HDTV, so 3,840 by 2,160. Everyone colloquially calls this "4K," though the technical term is Ultra HD. This has four times as many pixels as 1080p HD.

Which brings us to 8K. You guessed it: twice the horizontal and vertical resolution of 4K, for a whopping 7,680x4,320 and 33,177,600 total pixels. Not only is that four times the resolution of 4K, that's an incredible 16 times more pixels than 1080p.

TV resolutions

Resolution name Horizontal x vertical pixels Total pixels Other names Found on
8K 7,680x4,320 33,177,600 Ultra High-Definition (UHD), Super Hi-Vision, UHD-2 Concept TVs (so far)
4K 3,840x2,160 8,294,400 Ultra High-Definition (UHD) Most midrange and high-end TVs
1080p 1,920x1,080 2,073,600 High-Definition (HD) Smaller, less-expensive TVs
720p 1,280x720 921,600 High-Definition (HD) 32-inch and smaller TVs

Do you need 8K?

Not even a little. 

As we've explained many times with 4K TVs, there's a point of diminishing returns when it comes to resolution. The human eye can only see so much detail, and extra pixels beyond what you can discern are basically wasted. To get anything out of higher resolutions and their proportionally tinier pixels, you need to sit closer, get a bigger TV, or both.

Now playing: Watch this: Samsung's first 8K TV is an 85-inch beast
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It's rare that anyone gets a large enough TV -- or sits close enough to one -- to justify the need for 4K resolutions. 8K is excessive overkill… at least for a TV. If you're talking about massive theater-size screens like Samsung's Wall or Sony's Cledis, 8K would be amazing. But since 4K is hard to discern when comparing to a 1080p TV, 4K to 8K from 10 feet away will be pretty much impossible.

Based on the math of human visual acuity, you'll need to sit really close to an 85-inch 8K screen to get any benefit of the extra resolution. Carlton Bale's superb home theater calculator, for example, says you'll need to sit 3 feet or closer (to a screen that's more than 7 feet diagonal) to see all the detail of 8K, and 5 feet or closer to see the full benefit of 4K. In other words, from further than 5 feet away you won't be able to see any benefit of an 8K TV compared to a 4K TV. And that's at 85 inches. You'll need to sit even closer to smaller TVs to discern the benefits of 8K.

What about content? 

Without 8K content, an 8K TV is just a 4K TV with a few thousand dollars stuck to it with masking tape. Samsung talked up fancy "AI" upscaling technology on the Q9S, designed to improve the look of mere 4K and 1080p sources on an 8K screen. But to get the most out of all those 33 million-plus pixels, the incoming source needs to be 8K too.

There are three main aspects to getting any new format viewable in your home: the content itself, transmission and playback. The Samsung 8K TV and others that will surely follow represent the playback side, that is, the TV or projector in your home. That's the easy part.

Content is tougher. First off, there are only just a few cinema cameras capable of capturing 8K. Japan's NHK has been dabbling, and will likely transmit a significant portion of the 2020 Tokyo Olympics in 8K. There has been some 8K content shot at the last several Olympics, so expect even more. There are a handful of channels on YouTube that showcase 8K content, mostly nature documentaries and the like.

Red, one of the main camera companies used for Hollywood movies, has several models that can record in this resolution, as do a few others. Interestingly, there have already been feature films shot in 8K. Guardians of the Galaxy Vol. 2 was the first, followed by Mortal Engines, The New Mutants and a few others that are upcoming. Creating 8K content is more challenging, as the cost for these cameras, plus the computers and storage capable of dealing with hundreds of terabytes, if not multiple petabytes of information, do not come cheap.

red-monstro-vv-8k-camera-body

The Red Monstro 8K VV "Brain" has a 35.4-megapixel CMOS sensor, can record 8K video at 60 fps, has over 17 stops of dynamic range, and costs -- brace yourself -- $54,500. 

Red

Few standards, lots of megabits

The most difficult part will be transmission: getting this modicum of 8K content to your home. There is currently no standardized way to get 8K content to your shiny 8K TV. Presumably, as more content becomes available, a special app within the TV will get you access to this high-res media. This is likely what Samsung will have to do for you to be able to see anything in 8K on its 8K TVs. 

Sometime later, probably way later, the mainstream apps and companies, like Netflix, Amazon and Vudu will follow suit. Since there's little progress in getting even 4K widely adopted on cable and satellite, 8K is going to remain a rarity, to put it optimistically. At least for a while.

8K also presents another issue for the early adopter: the bandwidth required is going to be ridiculous. Most 4K content providers recommend you have an internet connection in the 20 Mbps range. 8K, even with everything else the same, has four times as many pixels. That doesn't equate exactly to a 4x increase in data or bandwidth, but, and this is just a ballpark guess, a connection requirement in the 40 to 50 Mbps range wouldn't be unexpected. Maybe you, dear CNET reader, have that kind of speed, but the vast majority of people do not.

hdmi-bandwidthcomparison.jpg

A visual representation of how much more bandwidth the upcoming Ultra High Speed cables can handle.

HDMI Forum

Interestingly, we've already got the physical connection thing sorted, if any 8K media streamers hit the market. HDMI 2.1 is capable of 8K resolutions and more. But before you rush out and stock up on HDMI 2.1-compatible cables, keep in mind there will almost certainly be a new standard between now and wide adoption of 8K. So those cables might be obsolete, despite their current forward-looking appearance.

Why, CNET, whyyyyy???

To put on my cynic hat, increasing resolution is one of the easiest ways to offer the appearance of higher performance. This is likely what Samsung is smoking, coming out with an 8K TV when there's essentially no content and no 8K infrastructure. 

LG, with OLED, has been taking all the picture-quality headlines. No doubt this rush to 8K is a way for Samsung to get some of the headlines back. Given how easy it was to market 4K as "better looking than 1080p," you can bet 8K will be marketed as the same.

Resolution is just one aspect of overall picture quality, and not one of the most important ones. Improving other aspects, like contrast ratios, overall brightness for HDR, more lifelike colors and so on, offer better image improvements but are significantly greater technical challenges. This is especially true for LCD technology, something Samsung is still strongly flogging -- all of its QLED TVs are just LCD TVs with quantum dots

It's relatively easy to create a higher-resolution LCD panel, but improving the other aspects of performance for that tech is a greater challenge. This is why OLED is a thing, and why many companies, including Samsung, are researching new technologies like true direct-view quantum dot displays, MicroLED and other technologies.

direct-view-qd

Direct-view quantum dot display.

Nanosys

Don't wait for 8K

So if you're thinking about buying a new TV this year, does this mean you should hold off? Well, if your current TV works, you should probably hold on to it regardless, but new 8K TVs shouldn't be a factor. For one thing, these early TVs will be very expensive. I wouldn't be surprised if the pricing is astonishingly high. We're also many, many years away from any sort of widespread 8K content. We arguably don't have widespread 4K content, and no one is talking about scrapping 4K to go directly to 8K.

The other aspect is a warning that will be seconded by countless 4K early adopters: There is no guarantee these early 8K TVs will end up being compatible with any future 8K standard. There are tens of thousands of 4K TVs that can't play any current 4K media content. Why pay exorbitant amounts of money on a TV that barely has any content now, and might not be able to play any later? Bragging rights, I guess, and if that's your thing, who am I to stand in your way? Just keep in mind that current HDR 4K TVs look vastly better than every first-gen 4K TV and cost a fraction of the price. 


Got a question for Geoff? First, check out all the other articles he's written on topics like why all HDMI cables are the sameTV resolutions explainedLED LCD vs. OLED and more.

Still have a question? Tweet at him @TechWriterGeoff, then check out his travel photography on Instagram. He also thinks you should check out his best-selling sci-fi novel and its sequel