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Why Ultra HD 4K TVs are still stupid

The flood of TVs with higher resolution than 1080p is inevitable, but at typical TV sizes, quadruple the pixels makes no difference in picture quality and are not worth the extra price.

Geoffrey Morrison

As we all expected, the big news at CES this year was Ultra HD 4K displays. It seemed that every TV manufacturer had one, ranging from massive LED LCDs to midsize LED LCDs to midsize OLEDs.

We've talked about this before, but now with more info, and definitive product announcements, let me explain in exacting, excruciating detail why 4K TVs are still stupid.

Allow me to start with the most important point:

1. I love 4K
It is my fault for trying to make a nuanced argument on the Internet. I have a 102-inch "TV" and sit 9 feet from it. I would love to have 4K. When I expand out to fill the full 10-foot-wide 2.35:1 screen, I can see pixels with some projectors. I look forward to more 4K projectors. Projectors are not TVs; 4K TVs are a waste. This is because...

2. The eye has a finite resolution
This is basic biology. The accepted "normal" vision is 20/20. In response to my previous articles on the stupidity of 4K TVs, many people argued they had better vision, or some other number should be used. This is like arguing doors should be bigger because there are tall people. Also, just because you have better vision, doesn't mean most people have better vision. If they did, it wouldn't be better, it would be average.

Try this. Go to the beach (or a big sandbox, or a baseball diamond). Sit down. Start counting how many grains of sand you can see next to you. Now do the same with the grains of sand by your feet. Try again with the sand far beyond your feet (like, say, 10 feet away). The fact that you can see individual grains near you, but not farther away is exactly what we're talking about here. The eye is analog. Randomly analog at that. So of course some people are going to see more detail than others, and at different distances, but 20/20 is what everyone knows, and it is by far the most logical place to start any discussion.

Is there some wiggle room thanks to variances in how people see? Yes, of course. Here's an awesome chart:

Carlton Bale

Let's skip ahead a step. Getting bogged down in the specifics misses the big picture. The eye does have a finite resolution, and if you want to argue it's better than 20/20, you're still conceding the point. You're just saying that smaller 4K TVs are viable. How much smaller? Well, not 50 inches. Probably not 60 inches, either. These are the sizes people are buying. Most people are buying even smaller TVs. Which leads to...

3. 84-inch TVs are never going to be mainstream
Never. Ever. Never ever. Like I said earlier, I have a 102-inch screen. I've also reviewed an 80-inch Sharp LCD. And let me tell you, it dominates the room. It's massive. There is a significant difference between a screen (effectively, the wall), and a Device of Unusual Size. Enthusiasts might be OK with this thing in their room, but most people won't. Ask your spouse. Ask your spouse's friends. Screen sizes have been inching upward, but not linearly with price. More specifically, the prices of big-big screens have fallen much faster than their sales have increased. I don't know what the upper limit is for what the average consumer decides is "too big" for their room, but I'm positive there is an upper limit, and this limit is far smaller than screens that need 4K.

I should clarify what I mean by "TV." I'm specifically talking about the televisions we know today. When OLED becomes something you can paint on your wall, or so paper-thin it hangs like a poster, then absolutely people will get bigger screens (presuming they're cheap). However, this is years (decades?) away. This future awesomeness is different than TVs of today. Will we still call them "TVs"? Yeah, probably, but their presence in the room will be radically different, hopefully because these future wafer-thin "TVs" won't have a presence in the room. They'll be part of the wall.

4. Viewing distance hasn't changed with HD, why would it change with UHD?
In the old days of 480i CRT tube TVs, people sat roughly 9 to 10 feet away from their TVs. There were good reasons for this (scan lines). Modern TVs offer significantly better resolution, so people can sit closer. Except...they don't. Most people still sit the same distance from their TVs as they did before.

Could people sit closer? Sure. A lot closer, actually. This ties in exactly with point No. 3. Sitting closer would be like getting a bigger screen, as it takes up more of your field of view. Just as people aren't getting as big a TV as they could, people aren't sitting closer, either.

So they can sit closer now, but don't. Why would anyone assume that because of UHD, people would suddenly sit closer. It doesn't make any sense. And just like with No. 3, I don't think most people would want to sit closer. Some of you might want to sit 5.5 feet from a 84-inch screen, but you are a tiny minority.

And speaking of viewing distance, this is precisely why comparisons to the Retina Display iPad are specious. The viewing distance is rather different between a TV and a tablet. Or, as President of DisplayMate Technologies Corp. Raymond M. Soneira says, your TV is already a Retina Display.

5. Why 4K?
Ah, now this is an interesting question. It's clear many seem to think TV manufacturers are some sort of altruistic entities that only do new things if there's a benefit to the consumer. How adorable, but no. Ultra HD isn't the "new technology" it appears. Modern TVs are made from huge sheets of "motherglass." From this big piece, companies slice up smaller pieces to make televisions. It's easier (read: cheaper) to make a big piece and cut it into smaller TVs.

Originally this was in case there was a problem with part of the glass, the rest could still be sold as TVs. When you read about "yields" as part of TV manufacturing, this is largely what they're talking about.

But manufacturing has gotten really good, so most of these pieces of motherglass are fully used. Instead of slicing up one piece of motherglass into four 42-inch 1080p LCDs, what if you just kept the whole thing as one piece? What would you have? You'd have an 84-inch TV. Use the exact same (or similar) drive elements/electronics and all the various bits, and you've got a 3,840x2,160-pixel, 84-inch UHD TV. Hey, wait.

You see, TV companies are pushing 4K because they can. It's easy, or at least easier than improving the more important aspects of picture quality (like contrast ratio, color accuracy, motion blur, compression artifacts, and so on).

6. 4K is easy to market
OK, so 4K is easier to manufacturer than an actual new technology ( OLED), but there's more to it than that. Ultra HD is an easy sell. It's a number, greater than another number; therefore it's "better." In the confusing world of televisions, simplifying "superiority" down to a single number is marketing gold.

This is just like megapixels on a camera. An 18-megapixel camera does not necessarily take better pictures than a 16-megapixel camera. I guarantee my SLR takes better pictures than a "higher-resolution" point-and-shoot. Numbers are easy to understand, and for nonenthusiasts, distilling a TV down to a single number is desirable. This was rampant in the early days of 1080p. I actually heard people say "I don't know what 1080p is, but I know I'm supposed to want it." And looking at a spec sheet in BigBuy, 1080p is more than 720p, so it's better, right? 4K is an easy sell: it's higher than 1080p. It's also an easy demo...

7. 4K makes a great demo
Our own Matt Moskovciak tweeted this at CES:

Exactly. Take a look at the picture at the top of this post. Better yet, look at this one:

Dennis Burger

Sexy bald head aside, when people talk about seeing 4K, they are way closer than they would normally be. Up closer, yeah, 4K looks amazing. This is, of course, how they'll sell in stores. People will walk right up to the screen and go "Wow!" This ignores points Nos. 2 and 4, but try to explain either one to a nonenthusiast. It looks neat, it has a number greater than another (point No. 6), and I'm sure it will sell.


8. The lack of content is not the problem
So much coverage has focused on the lack of 4K content. This is not the issue. It was years before HDTVs had meaningful amounts of content. Presuming points No. 2, 3, and/or 4, quality upconversion can add some detail to 1080p content, making it appear a little sharper than nonupconverted 1080p on a like-size 1080p screen. Again, this is presuming you're close enough to see it. Upconverted content is not the same as real 4K content, but it's a step.

There are other, better uses for Ultra HD TVs as well. Passive 3D is far more pleasing to watch than active 3D, but you lose half the vertical resolution (i.e. 1,920x540 pixels per eye with 1080p). This is still the case with passive 4K TVs, but you can afford to lose it. Passive Ultra HD TVs are still greater than HD resolution, at 3,840x1,080 pixels per eye.

This also opens up possibilities for viewing two different programs on the same TV. Using polarized glasses that block the same lines for each eye, two different 3,840x1,080-pixel programs could be enjoyed by different people on the same couch. So the Missus could watch the game while you watch "The Bachelor" (presuming you have two cable boxes or an antenna). This is somewhat possible now (though this is half-HD resolution) and Samsung demoed a prototype version at CES, so this isn't strictly a 4K thing, but it is an interesting use.

9. There are bigger issues
My biggest complaint about Ultra HD is what it doesn't address. Resolution is not the most important aspect of picture quality. Nor, as we've discussed, is it even a problem with current picture quality. How about improving contrast ratio, color, and compression artifacts? These all have a significantly greater effect on picture quality than resolution.

I'll add another problem to the list of things 4K doesn't address: motion resolution. All LCDs suffer from motion resolution problems, in many cases, losing upward of 40 percent of their visible resolution when anything on the screen moves. All announced (and most of the previewed) Ultra HD displays are still just LCDs, with all of that technology's shortcomings. These so-called "next-generation" televisions will still have poor off-axis picture quality and mediocre contrast ratios. They'll likely have poor picture uniformity, too, as many models are edge-lit. True, they all have higher refresh rates, but without motion interpolation, higher refresh rates do little to fix motion blur. If the drop in resolution with current LCDs is any indication (and No. 5 shows it is), these "2160p" TVs will resolve something like 1,296 lines with motion.

Perhaps this is why nearly every demo at CES of 4K and 8K TVs showed slow pans and still images. Check out "What is refresh rate?" for more on motion resolution.

Will some models offer methods to combat motion resolution that don't cause the dreaded Soap Opera Effect, like black frame insertion? Many will, yes, but not all.

10. Ultra HD OLED
Sony and Panasonic previewed 4K OLED TVs at CES last year. Since OLED does address the contrast ratio issue, I have no problem with 4K OLED. When I saw LG 4K OLEDs at the CEDIA Expo, they looked amazing. This is because OLEDs create a better overall picture, regardless of their resolution.

During the CES lest year I tweeted the following:

You see, I want us all to have a new car, not just get stuck with our aging Pintos or fermenting Omni GLHs with a slapped-on set of shiny new Pirellis. (And I'll leave it up to you to decide which one of those is LCD and which is plasma.)

11. There are no standards
This is, perhaps the biggest problem with Ultra HD displays available right now/soon. HDMI 1.4, the most common standard, allows for a maximum of 4,096x2,160 pixels at 24fps. Granted this is slightly higher than the 3,840x2,160 of the current crop of Ultra HD displays, but it is not enough to do 4K 3D. It's not enough to do higher frame rates, either, which may or may not come into play (though with computers, it certainly will).

HDMI 2.0 will offer more bandwidth, so higher resolutions and frame rates can be transmitted over everyone's favorite cable, but that will require different transmitter and receiver chips. This won't be a software upgrade, many of the current Ultra HD displays are already obsolete. Remember, this isn't as simple as swapping out a new cable; the hardware in the TV won't be able to accept the higher data rates. I don't hear any manufacturer mentioning that upgrade path for their $20,000 televisions.

When there is a final standard, who knows what it might have? Maybe they will improve some aspect of color (either in better color depth or in a wider color gamut or both). These Ultra HD displays won't be able to take advantage of that, either.

12. 4K TV is inevitable
When I first starting pointing out most people didn't need 1080p TVs (in the age of 720p flat panels), I knew -- and said at the time -- that 1080p was inevitable. I was just trying to save people some money. That's all I'm trying to do here. Nothing I say will have any effect on what the corporate giants decide to force on us mortals. I'm just trying to point out that increasing resolution in itself is not the improvement in picture quality it "appears" on paper. I'm trying to point out that even when these TVs come out, your money is better spent elsewhere. What I want is better, cheaper TVs and better picture quality for everyone. So thank you to everyone who made personal attacks against me for pointing out what should be obvious (that your favorite TV company is not your boyfriend).

Update: November 13, 2014

13. Nooooope
Since I wrote this article nearly two years ago, there are vastly more 4K TV available. There's also a lot more marketing money hyping 4K. But the facts haven't changed, and what I wrote then still holds true: In smaller screen sizes, 4K just isn't worth the money.

This year's TVs still haven't fully sorted out HDMI 2.0 and HDCP 2.2, not all have HEVC (H.265) decoding, and none have any of the potential drool-worthy benefits of Rec 2020.

Things like High Dynamic Range, which could drastically improve picture quality, are still being overlooked for the sake of the almighty resolution number.

And OLED! 4K is definitely slowing the coming of OLED, even if LG showed a few models this year.

Eventually all TVs will be 4K, just as all (or nearly all) of today's TVs are 1080p. That's just how it works. There will be 4K content too, eventually. Wait a year, and the shiny you've got your eye on now will be cheaper, better, and actually able to play back some real 4K content. Save your money.

14. Beware what you see
Vast numbers of commenters have mentioned something that's worth addressing. The showroom floors of Best Buy, Costco, and the rest, have never, in their history, been adequate places to judge the picture quality of a television. Yet somehow, with the advent of 4K, they suddenly are? Illogical, but many are holding it up as truth.

Watching an immaculate 4K signal (that you can't get at home), on a $5,000 television, while it sits among $800 non-local dimming LCDs running barely HD feeds, is not a far comparison. Nor is it indicative of what a 4K TV will look like in your home, running mediocre 4K streaming signals from Netflix or Amazon.

And along the same lines, ultra-high resolution tablets and smartphones prove my point about resolution, not disprove. The closer the screen is to your eyeballs (or the bigger it is), the more resolution you need. That's all I've been saying from the beginning.

15. More voices
I'm not the only one talking about this anymore, thankfully.

CNET's own David Katzmaier just wrote Is now the time to buy a 4K TV?.

Check out Chris Heinonen's 4K Calculator to see if you'd benefit from a 4K TV given the size of the TV you're considering, and where you're sitting.

The Wall Street Journal weighed in.

Cinematographer Steve Yedlin (Looper, The Brothers Bloom) wrote an interesting blog post about 4k..

And oh yeah, Consumer Reports did a side-by-side comparison: 4K content on 4K TVs, and the same movie on Blu-ray with a 1080p TVs. They found, "...yes--the 4K films did show a noticeable bump in image detail compared to their HD counterparts. But there's a caveat: These differences were not present on all movies, and were visible only when viewed less than 2 feet from the screen, and even then only on certain scenes. When I moved back about 7 feet from the displays, differences between 4K and HD content were not discernible to any meaningful degree."

Couldn't have said it better myself.

Bottom line
Nothing I say will stop Ultra HD. Look no further than our own CES coverage for proof of that. TV manufactures are smelling margin like blood in the water. This is something they can do, now, and for a profit. So it's happening, whether it's necessary or not. Instead of improving aspects of the image that need fixing, we get 4K because it's easy to do, easy to sell, and easy to demo. Awesome.

So before you jump down my throat for being "anti-technology" or "anti-innovation," understand I just want better picture quality in the home, for less money, and Ultra HD 4K is not the best way to do it.

Update: November 22, 2015

A lot has changed in the nearly three years since I first wrote this article. Prices have fallen, new technologies have come out, and there's more (though still not a lot) of 4K content. Today, the best TVs on the market have local dimming, HDR, and Wide Color Gamut... and they also happen to be 4K. Even the best mid-range televisions are 4K. So at this point, if you want a TV that looks good in general, it's going to have Ultra HD resolution (with some exceptions).

So for all to behold, 4K TVs are no longer stupid, and here's why (i.e. read that article first before you comment).

Got a question for Geoff? First, check out all the other articles he's written on topics like why all HDMI cables are the same, LED LCD vs. OLED, active versus passive 3D, and more. Still have a question?Send him an e-mail! He won't tell you what TV to buy, but he might use your letter in a future article. You can also send him a message on Twitter @TechWriterGeoff or Google+.

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