The world's first 8K TV broadcasts are now live - here's what that means for you

Japan's NHK has started to broadcast TV in 8K resolution ahead of this weekend's Summer Olympic Games in Rio de Janeiro.

The public broadcasting organization is sending the extremely high-resolution video to its "Super Hi-Vision" satellite test channel, which launched on Monday and also includes 4K content.

The channel isn't available for Japanese residents to watch at home, so NHK has set up six public viewing stations across the country for those interested in the tech. It'll broadcast footage from Rio Olympics, highlights from the 2012 London Games, and various concerts, among other things.

NHK has been preparing this test for years. The larger hope is to implement the technology nationwide in time for 2020 Olympics in Tokyo.

The 8K spec itself broadcasts at a resolution of 7,680 x 4,320 pixels. That's about four times the resolution of most 4K TVs, which are still not fully ubiquitous today, and 16 times the resolution as 1080p HDTVs. The "Super Hi-Vision" format is also capable of advanced 22.2-channel audio - that's bigger, deeper, better surround-sound audio.

TV makers like Samsung, LG, and Sharp have showcased 8K panels at events like CES for the past few years. In late 2015, Sharp actually put one on the market in Japan, but it cost well over $100,000.

This is all exciting tech, but it's worth remembering that, on its own, 8K will never mean much to the average TV user. Apart from the usual challenge of getting content makers to actually adopt the format, it's physically impossible for the human eye to see the benefits of 8K under most circumstances.

This is still the case with 4K, too. This chart from Carlton Bale has been passed around for awhile now, but it hasn't become any less true. From just five feet away, you'd need an 80-inch TV to start seeing the added sharpness. 80 inches! Unless all TV manufacturers suddenly become charities, TVs that big will never adorn most people's homes. People aren't sitting closer to their 50-inch TVs, either; nor should they.

This isn't to say Ultra HDTVs are pointless, just that resolution alone isn't why you should buy them. 4K is an easy buzzword to sell, but it becomes much less of an important, tangible thing once you hit a certain threshold. (Things like motion blur, contrast, color gamut, and black uniformity are more significant, but harder to grasp.) If 4K is already breaking through that threshold today, something that adds four times the pixels will turn it to dust.

There'll still be some cases where 8K might make sense - VR, perhaps, or just enormous displays - and there's still plenty of room for today's TVs improve. Just don't expect NHK's breakthrough to be a big boon for your living room anytime soon.