Is 4k an improvement for people with normal vision?

[LaurV]

One of many monitors we use at home is a 24" HP with 1920x1200, which is ages old (about 2006 or so), we bought it long time ago and paid a fortune for it, at the time it was some rare bird, with HDMI connection which also supplies power, etc (however, we never connected a compute stick to it, because we no not have one, but we will accept donations for Christmas )... Now, it looks just like a heavy piece of furniture, compared with newer stuff, it has built-in speakers and a camera we never used, and ugly (according with current standards) wide bezel around the screen (about 3 or 4 cm !)... It has some features to flip and rotate the screen (physically, it is mounted on a rotational ball) which we also never used (it may be good for a photo studio, to edit some diva pictures in portrait mode, but not for our daily stuff as writing posts on mersenne forum), and a light sensor to reduce the brightness if it is dark in the room. This light sensor, we had to cover it with a black tape, so the monitor believes that it is always dark, and keeps the brightness to minimum, but even so, it seems much too bright for us. We can not adjust the brightness lower without losing colors, so we negotiated a deal with it to accept it as it is... If we get very close to the screen, we can see the pixels with bare eyes. We also have few other monitors around, mainly old 19" 1280x1024, which are worse, but yet, at the distance we use them (about 50 cm or more), they look good.

We have few of 22" 1680x1050 on the desk at job - they are very nice to use, the pixels are a bit larger, but at about 40-50 cm, we can't see individual pixels. The IT people offered us higher resolution monitors but we didn't want to change, which made our younger colleagues very happy, and they took the newer monitors with higher resolution.

Making LCD modules is our current job, so we have a magnifier glass around, using which we can see all the pixels, no place to run, no place to hide...

[VBCurtis]

Originally Posted by ATH

Not many people uses screen sizes between the largest tablets at 10''-11'' and the smallest monitors at 22''-24'', not like 20-30 years ago when all monitors was 13''-17''.

Except nearly every laptop in existence? I think those are still pretty popular.

[ATH]

Originally Posted by VBCurtis

Except nearly every laptop in existence? I think those are still pretty popular.

Yes, I did not really count in laptops. At my work most laptops spend all of the time in one docking station or another with external 22+'' monitors. People that travel of course use the laptop screens, but I almost never do myself, but you are right.

[Mark Rose]

Originally Posted by jasong

Mind you, I'm not asking if it's worth the extra money, I'm asking if it's even possible for the average person to see the extra detail. I read an article saying that 4k looks the same as 1080p to people with normal vision. I originally thought they were wrong, but now I realize the superior quality of the video in the store might've been more about color vibrancy than detail.

So I now have a $500 4k monitor of dubious value and a question. Do you guys see a difference between 4k and 1080p?

As others have mentioned, screen size and distance matter, but so does the definition of normal vision.

"Normal" vision, 20/20 or 6/6, is kind of arbitrary: the best human vision is around 20/9 or 20/8, which allows such a person to see things a little more than twice as far away as "normal". The cutoff for "normal" is basically when a person's visual acuity does not cause trouble in daily life. Many things can affect the ultimate seeing resolution of the eye, including the size of the eye, the individual's cone cell density in the retina, etc.

With visual training, some people are able to improve their visual processing to 20/7.5. I've used an app called GlassesOff and found improvements in contrast and edge perception. The brain is amazingly plastic. The brain can only do so much with the input it is given though, so it's certainly better to start with vision correct (glasses, laser).

Prior to eye surgery, I was about 20/50. Now I'm about 20/9. For me, 4k would definitely make a difference in most situations. For my parents, who probably have at best 20/20 when wearing glasses, I doubt it would. DVDs rapidly replaced VHS because most people could see the difference. This hasn't been the case with BluRay because fewer people can see the difference (and not everyone has a large TV). The move to 4k is even slower, for the same reasons.

It's actually pretty simple to tell if you were to benefit: put something on a 1080p that has a diagonal or curved line. If you see the jagged edge caused by pixelation from your normal distance, then there's a good chance you would appreciate 4k. If it looks perfectly sharp, then no.

My laptop has a 169 ppi 1080p 13" screen and I wish it were more like 200 ppi so I could make the fonts smaller and see more at once. 1440p in 15" would be good. Similarly, I use a 109 ppi 1440p 27" screen at home and work, and I really want to switch to 4k in a 24" format (184 ppi).

My 55 ppi 1080p 40" TV is 8 feet away from me and I see pixelation. Most people wouldn't. It doesn't annoy me enough to buy a 4k TV though. I also try to sit in the back third of movie theatres to avoid the pixelation there.

I wish my hearing were as good.

[fivemack]

I was surprised how much nicer text (generally lists of JIRA requirements) looked on a large 4K screen compared to projection, but I suspect the projection was at 1280x720 and so there's a factor three better resolution in each direction.

I have a 4K thing-sold-as-a-television, attached to my XBox which can in principle play 4K BluRay content; I don't know whether I can't tell the difference or whether I have the wrong kind of cable and it's silently falling back to 1920x1080.

[LaurV]

Originally Posted by fivemack

I have a 4K thing-sold-as-a-television, attached to my XBox which can in principle play 4K BluRay content; I don't know whether I can't tell the difference or whether I have the wrong kind of cable and it's silently falling back to 1920x1080.

Ages ago when we were working in IT, and LCD screens started to substitute the classic CRT monitors, we used to do the following simple test to check if the VGA cards and the monitors work properly together: open notepad, select arial font (should be default) and stick your finger on the "L" key to type few rows of "lowercase L" letters (possible make it faster by using ctrl+a, ctrl+c, and a couple of ctrl+v to copy/paste text already inserted). Make half screen of it. Like this:

lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll

If your resolution is right and your monitor gets well with your graphic card, then all lines are equal, equally-thick, equally-spaced, and there are no gray/black dots or circles in the corners or in the spaces between letters or rows. The white space should be white. If you see gray dots or butterflies flying over the field, then your resolution and/or refresh rates are wrong. You would be surprised how many defects such a simple test can detect. Try setting your resolution to some the monitor is not designed for, and you will see immediately the difference in how the rows of L's look. This black/white tight pattern is quite stressful for the LCDs, and it will reveal the quality of your monitor (cross talk, etc). Later on, we also implemented similar "checkered flags" tests in our production too (we produce LCD modules for industrial use) and they worth the money....

[CRGreathouse]

Wow, nice test! I don't see any dots or circles, and the lines are equal, equally-thick, and equally-spaced, but there's strong color banding from left to right: green, red, purple, blue, repeating 6 or 7 times.

[Nick]

Time for a new version?
https://en.wikipedia.org/wiki/Test_Card_F

[chalsall]

Originally Posted by Mark Rose

As others have mentioned, screen size and distance matter, but so does the definition of normal vision.

Indeed.

With glasses, I have ~20/12 vision. And I always annoy my opticians when I go in for my yearly check-up and glasses replacement, because I always refuse their recommendations of progressives and other add-ons like anti-glare, photon-responsive shading, et al.

"Please listen to me very carefully. My workstation's four 1920 by 1080 pixel 53 cm diagonal monitors are ~62 cm away from my eyes. I don't mind having to use other glasses for distance and/or when outdoors. Please sell me what I'm asking for, or I'll go somewhere that will.

I have also learnt to take in my previous prescriptions for each exam, as it speeds up the process (they simply dial in the previous settings, and then determine if anything has changed). I also insist that I get a copy of the prescription just given -- they don't like doing this, but have to if asked.