See my Mac wish list.
The HDMI 2.1 standard has been issued. It will take at least a year and possibly 2-3 years for computer makers like Apple to implement it. I hope to see a 34-inch iMac Pro 8K in 2018, but I give that low odds due to panel availability. But at the least, I hope that the vaporware new Mac Pro will supprt HDMI 2.1, which would make it worth waiting for and buying.
All sorts of things need to happen, not the least of which is graphics support 4 times more powerful than today’s 5K-capable computers, new cables, development of 8K and 10K panels at semi-reasonable prices, etc.
Even today, the new Apple iMac Pro remains stuck at 5K, probably because of the lack of suitable 8K panels (Apple can custom support 8K just as with the original iMac 5K).
TechConnect.com has an excellent summary of what HDMI 2.1 will usher in, in HDMI 2.1 specs and features: Everything you need to know. In a nutshell, a new wave of quality far beyond anything today—a huge leap. Hardware will take years to catchup.
4K = 8.3 megapixels
5K = 14.7 megapixels <== exists today in iMac 5K and is fantastic
8K = 33 megapixels
10K = 59 megapixels <=== more than the Nikon D850, Hasselblad X1D, Fujifilm GFX!
One reason I refuse to shoot any camera less than 42/45/50 megapixels now, is that even a 36-megapixel camera won’t come close to filling a 10K screen (10240 X 5760 pixels), and just squeaks by on an 8K screen(7680 X 4320 pixels). Thus, I have zero interest in shooting 16 or 24 or 30 or 36 megapixel cameras that will fall far short of filling the screen, because within 3-5 years we will have 8K at reasonable prices. But perhaps the industry will leapfrog 8K and go directly to 10K.
For still photography, you will need to master focus stacking to not see how even a small shortcoming in depth of field results in less than full detail. Lens performance will become even more important.
From the TechConnect.com article:
Increased bandwidth is the most salient improvement HDMI 2.1 delivers. We're talking a staggering 48 gigabits per second, compared to the 18Gbps that HDMI 2.0 can handle. That bandwidth bump makes possible all of the larger numbers you'll see in the rest of this story: 8K and 10K video resolution, 4K resolution with a 240Hz refresh rate, and so on.
When HDMI 2.1 does arrive, it will be in high-end video cards aimed at gamers, and in medical, industrial, and scientific imaging systems. As the 2020 Olympics will be broadcast in 8K, we wouldn't be shocked to see an 8K TV appear before then.
I saw 8K earlier this year at CES (unbelievably detailed even on a huge screen). It’s just a matter of time before the economics work themselves down to reasonable pricing levels.
Meanwhile, 4K and OLED are all the rage.