Isn't 8K too much?

It requires a combination of at least three genetic flukes for humans to achieve extreme levels of visual acuity:

1) Perfect ocular shape and optics to begin with

2) Higher than normal cone density on the retina

3) Outstanding transparency inside the eye

Only a very small percentage of people get all the flukes combined, so it's very rare. Yet we should keep in mind that right now we are quite a few billion people on the planet...

Remember that some birds like falcons have "ordinary" visual acuity in the order of 20/2, or about 10x sharper than the "normal" 20/20 vision of humans. But even keeping the pride of our species with respect to eyesight sharpness in check, it is actually not so rare to find people with better than 20/20 vision. Let's see briefly how "not rare" that is.

Roughly, about 35% of the adult population has at least "normal" or 20/20 vision without glasses. But close to 10% of the US population has 20/15 (better-than-normal) vision. (Later addition: a nice distribution of visual acuity is shown in Fig. 4 of this other paper.)

In fact, 1% of the population achieves 20/10 vision. That's twice as good as "normal vision." The human record seems to be even slightly better: around 20/8. That means, being able to read at 20 meters what most (those with 20/20 vision) can only read at 8 m or less.

On the other hand, approximately 64% of adults wear glasses, at least in some developed countries. Yet we can imagine that the eyesight of glass wearers, with their glasses on, falls roughly on a normal distribution bell peaking around 20/20? So even if just 1/3 of them (us) can see slightly better than 20/20 with glasses on, that would represent about 20% of the total adult population. Let's assume that is a bit too optimistic, so to be conservative, let's make that just a 10%.

Adding that to the 10% who already achieve at least 20/15 vision without glasses, we can estimate that roughly 20% (about one in every five people,) exhibit a visual acuity that is clearly better than the "normal" 20/20. Notice, that's regardless of whether they wear glasses or not.

This study mentions average FVT visual acuities of 1.82, so closer to 2x the "normal" 20/20. Not sure what population samples they used there though.

So as a sort of disclaimer, in spite of my long previous post explainin when and why 4K might not offer any visible improvement over Full HD or even plain HD, we should not forget the fact that there are cases in which the benefits of a higher resolution can indeed be seen and be pertinent and enjoyable. The obvious examples: you simply sit closer than the ideal viewing distance for your visual acuity, and/or you do have in fact better than normal visual acuity, which as we just saw, is not so rare after all.

But keep in mind, that is not really a case in favor of 4K or 8K or even higher resolutions.

And now to honor this post's title: Japan's public broadcaster NHK has recently announced TV broadcasting at 8K.

Well, nice try, Japan. But isn't that too much?

Let's be clear: an absolute given resolution is never "better" or "wrong" or too much or too little in and of itself. Again, it might be too much, or satisfactory, or too little, depending on a combination of factors, namely pixel size, viewing distance, and visual acuity (check said previous post for all the details if needed.)

As if it wasn't already obvious from my posts on resolution, I don't think 8K for broadcast TV might be such a great idea, even for Japan (they pioneered the use of higher resolutions for broadcast TV before anybody else in the world quite many years ago,) and even for those lucky few with the three flukes combined and outstanding 20/8 vision. A very high resolution can be adequate in some use cases, but likely, it can also not be so, and a big waste. And there's quite a lot more to high resolutions that just being potentially useless or unnecessary and wasteful in some common cases.

Higher resolutions are very costly in terms of compression and bandwidth requirements (which in turn can deteriorate image quality very very quickly, and also most horribly and catastrophically, when not properly taken care of.) For a given bandwidth, the higher you go in resolution, the more you must sacrifice frame-rates, which will deteriorate the fluidity of motion. This has major implications for anything with fast moving images, like sports broadcasts, or in particular, video games. But even most importantly, resolution is only secondary after contrast and color, for ultimate picture quality.

The current trend in cell phone manufacturers, offering flagship models with cameras that have smaller pixel counts than older models (even some older non-flagship ones,) yet offer higher image quality, should give a clear hint already: people are starting to care about better pixels instead of more pixels, and are not falling so easily for the earlier and simpler "more pixels = better" marketing bull.

Well, but Japan, or at least NHK, seems to think otherwise. (Japan's Sony, on the other end of the bluff spectrum, recently offered its flagship Playstation 4 Pro console with a rather weak and disappointing claim in the 4K gaming arena.)

In any case, let me leave it at that for now as far as this post goes. I'll be talking more about Japan soon in an upcoming post, not only about this specific 8K move, but also about the history of TV and the current standing of Sony and Panasonic (Japan) vs. Samsung and LG (South Korea.)

There was a slogan that got advocated when the CD standard was finalized: "Perfect audio forever." With respect to picture quality, we could say the ultimate aim has been analogous for a long time: Perfect Image Quality Forever. Manufacturers and technologies have gone through up and downs, but they have been moving overall in that same direction. The fact is, display manufacturers and technologies have been able to provide outstanding, never-before-seen picture quality in consumer level displays this very year, in 2016. Pretty much anything from 2015 and before has been clearly left in the dust and very soon obsolete. There are very good reasons for excitement about display technologies and picture quality precisely right now and from now on, and that is really great news. (But 8K broadcast TV is not one of those great news, imho.)

As a sneak peak, I'd like to quote DisplayMate's assessment of a 2016 flagship OLED TV (For the record, I have absolutely no relationship with any of the companies mentioned in these posts.)

"In terms of picture quality the LG OLED TV is Visually Indistinguishable from Perfect. Even in terms of the exacting and precise Lab Measurements it is close to ideal, and it breaks many TV Display Performance Records. (...) far better than the best Plasma TVs in every display performance category, and even better than the $50,000 Sony Professional CRT Reference Studio Monitors that up until recently were the golden standard for picture quality. In fact, based on our detailed lab tests and measurements the LG OLED TV has the highest Absolute Color Accuracy, the highest Absolute Luminance Accuracy, and the highest Contrast Ratio with perfect Black Levels of any TV that we have ever tested, so it even qualifies as a Reference Studio Monitor."

Did you notice the bold text there? These pros talk about picture quality, and mention things like color, luminance, contrast, and black levels... But they don't even mention *resolution* there. Hmm... Wink wink ;) 

"Perfect", or let's say at least technically flawless displays are already available and might be bound to become pretty much a commodity rather soon, on cellphones as well as on computer monitors and large panels/TVs. Content makers and distributors have to bring up the image quality of the content they offer accordingly, no doubt about that. But to get there, moving up to wider contrast and wider color space standards is much more important than bringing up the resolution at the likely expense of frame-rates.

In any case, more on all of this in the next post.