Goto Costco and get a 55" tv, built-in speakers.
...and enjoy looking at those huge blocky pixels!
Seriously - it's not an entirely bad idea, but there are swings and roundabouts. If you use it at a typical "arm's length" distance, the UI in 1:1 "looks like 3840x2160 because it is" mode will be very usable, you'll get ridiculous screen real estate and you can stop fretting about scaled modes
but you will definitely be able to see pixels. If you move it twice as far away to get it past the "retina" distance so you can't see pixels (a) it's gonna fall off the end of your desk and (b) you'll probably be back to using scaled modes so you can read the UI (your eyesight may vary).
Aside:
"Retina" is an Apple trademark that they can apply to taste, but it does have some hand-wave-y basis in reality - the resolving power of the
typical human eye is about 1 arc minute or 0.0003 radians - which is the basis of the test for 20/20 vision. That's an angular measurement, which means the size of what you want to see divided by the viewing distance*. So to get the minimum pixels size for a "retina" display you have to make an assumption about the typical viewing distance, divide the pixel size by that, and see if it's under 0.0003. So, for an iPhone that you typically hold about 10-12" away from your face, it works out that the minimum pixel size is between 1/333"and 1/277" - or about 300 ppi.
Hence, once the iPhone hit over 300ppi, the "retina display" was born - although the idea actually dates
at least back to the 1980s when Apple released the LaserWriter which had a resolution of 300dpi (and people typically read A4 printed pages from 10-12"...)
Once you have "300ppi at about 1' = retina" then it's simple: double the distance, halve the minimum PPI. A 27" 4k UHD screen works out at about 160 PPI and you probably view it from about 2' away - at that distance anything over 150ppi is "retina" so you're good. That 55" TV is only going to be about 80 ppi, so you'll have to view it from 4' away to get "retina". Apple's 5k and 6k displays at 220 ppi are
very comfortably into the "retina" zone.
But, that is all very very
very hand-wavy: 20/20 vision is
typical - not best, not minimum and many people can do better or worse... and the human eye isn't a simple pinhole camera with the same angular resolution at any distance, not to mention all sorts of weird perceptual issues depending on what it is you're trying to evolve, so it's all very, very ball-park and "your mileage may vary".
(* pedant note - that assumes the viewing distance is much greater than the size, but far worse crimes against precision are being committed here)
www.rtings.com
