which resolution is human eye limitation ??

[Prox1ma]

For me personally it comes down to viewing distance and display size. I sit around 2 feet from the display. I couldn't see much of a difference between 1080p,2k and 4k in my old 768p 19inch display. After switching to the 278q, I now realize how bad 1080p can look in 27 inch display at this viewing distance. Now I have to find 2k or higher content (which is not very easy to find) to view 

[Jtalk4456]

none of this pixel count, dpi, or resolution matter anyways!

RTX is all that matters!!!!

[Sakkura]

11 minutes ago, Xilefian said:

Sorry about this, I apologise if you feel this is an unwarranted correction, but DPI and PPI are equivalent. DPI = dots per inch, which comes from the printing industry's metric for resolution. PPI = pixels per inch. A pixel is assumed to be a dot, and a point is also a dot, so DPI is interchangeable.

 

As a quick example of this interchangeability, the Android operating system API uses "DPI" for all its pixel resolution definitions: https://developer.android.com/training/multiscreen/screendensities

Microsoft also use DPI: https://docs.microsoft.com/en-us/windows/desktop/api/shellscalingapi/nf-shellscalingapi-getdpiformonitor

 

Apple calls their pixels "points", but they never talk about density so you shouldn't see official Apple material with "points per inch" written anywhere.

 

Actually, I'm not aware of any software SDK for any platform that uses "PPI", I have definitely see "pixels per inch" or PPI in online 3rd party material on the web, but as far as I'm aware all platform APIs use "DPI" (or nothing at all, in the case of Apple).

 

This is all semantics, so it doesn't actually matter, but it would be incorrect to say that "VR headsets do not have DPI, they have PPI" because PPI = DPI and everyone uses DPI.

I much prefer DPI as it is something the print industry has used for decades, so makes sense that displays are also measured in DPI - if we consider a single addressable pixel as a "dot" (which is reasonable, we've been doing that since colour television).

LCDs (or typical OLED displays) do not have dots, they have pixels made up of subpixels. Printing is entirely different from display technology, they don't even use the same color model (CMYK vs. variations on RGB).

[Xilefian]

16 minutes ago, Sakkura said:

LCDs (or OLED displays) do not have dots, they have pixels made up of subpixels. Printing is entirely different from display technology, they don't even use the same color model (CMYK vs. variations on RGB).

The computing industry does call single addressable pixel units "dots", I did provide evidence of this in my previous reply in case you missed those links. This likely comes from the CRT television days, where "dots" is used to describe the scanning resolution on a single horizontal line.

 

Colour reproduction is unrelated to display metrics, however interestingly there are displays that use the CMYK colour scheme as they are based around pigments just like printing (look up Electrowetting displays), so citing the CMYK as the difference between print and electric displays is no longer a reliable thing.

 

I absolutely agree that sub-pixels messes up everything here. I've done a fair amount of work with sub-pixel addressing in raster graphics, I hope that pixel geometry will eventually become a display metric that can be queried by a display adapter, but even if that day comes we'll still have a hold-over with the RGB single-addressable-pixel as the main unit for computer colour graphics, which as I said is what the industry calls the "dot" in DPI, so I don't think DPI is going away.

[Sakkura]

7 minutes ago, Xilefian said:

The computing industry does call single addressable pixel units "dots", I did provide evidence of this in my previous reply in case you missed those links. This likely comes from the CRT television days, where "dots" is used to describe the scanning resolution on a single horizontal line.

 

Colour reproduction is unrelated to display metrics, however interestingly there are displays that use the CMYK colour scheme as they are based around pigments just like printing (look up Electrowetting displays), so citing the CMYK as the difference between print and electric displays is no longer a reliable thing.

 

I absolutely agree that sub-pixels messes up everything here. I've done a fair amount of work with sub-pixel addressing in raster graphics, I hope that pixel geometry will eventually become a display metric that can be queried by a display adapter, but even if that day comes we'll still have a hold-over with the RGB single-addressable-pixel as the main unit for computer colour graphics, which as I said is what the industry calls the "dot" in DPI, so I don't think DPI is going away.

Large parts of the industry using sloppy terminology doesn't really make it correct.

[Sauron]

The number of pixels on a screen is just one parameter... you're not accounting for the size of the screen and how close or far you are from it. You won't see the pixels on a 4k 5" screen from 3 metres away, but you'll see them in an 85" screen 1 meter away.

[Tamesh16]

4 hours ago, sohail14 said:

day by day technologies improving especially for monitor and tv recently they anounce 8k monitor even 16k also coming 64k resolution coming feauture so which resolution is human eye limitation and what resolution maximum i can see detail??

it really depends, cause a large 8k monitor might be pixelated compared to a small 1080p , so distance ,size, resolution, your own ability to tell the difference, 

retina calculators can give a good idea, but persons accustomed to high resolutions can tell difference beyond retina, as proven by linus' previous video

[pipnina]

Measuring the angular resolution of the human eye should not be too difficult...

First off, the Rayleigh criterion puts a limit on how close two things can be to each other before they become indistinguishable. For the human eye that is either 27 arc-seconds (27/3600ths of a degree) when fully dilated or 82 arc-seconds when in a well-lit room or in broad daylight. Bright screens likely put the eye closer to the 82-second mark so I'll go by that.

 

82 arc-seconds is equal to 0.0004 radians. Which means that the physical limit (assuming perfect optics and retinal resolution to perceive it) That you could see the distance between any two pixels more than 400 microns (just under half a millimetre) apart when sat 1 metre away from the screen.

 

I took some photos with my macro lens of my 1080p/24in monitor, it has 333 micron pixles based on the half-mm ruler I placed in front of it. Sitting 1 metre away I had no chance of seeing even any aliasing, let alone pixels. It isn't really surprising that the human eye is not diffraction limited.

 

The clipboard icon on my system tray however is extremely sharp, and sat 1 metre away I figured that the lines between the icon's pixel art lines of text were starting to blur together. It is a two pixel gap between each line (i.e. 666~ microns). So I would presume that, as far as detail is concerned, the limit for human eye resolution is approximately 0.67mm per metre. When pixels are concerned, perhaps a screen resolution that meets twice this criteria (i.e. my screen's 333-micron pixels @ 1 metre) is ideal.

 

I tend to sit considerably closer to my screen however, so to achieve that same scale at 50cm I would need a 4k monitor.

 

Bit of a sketchy estimate, but it does have some math so critique away!

[Guest]

The photoreceptor responsible for seeing colour, the cones, are responsible tor spatial acuity and hence for the number of pixels that you can distinguish. The brain uses a comparison between two cones to suggest this acuity, and with a density of 150,000 cones / mm^2, we can assume that you could potentially see 75,000 pixels/mm maximum, however due to the brain being a funny wee thing and we cannot interpret that much information (and is not in our field of vision). Now also remember these cones need to react to light, so if your eye lens is out of shape in any way etc then the light is not being refracted to the cones and rods and its information will not be transmitted to the brain. 

[KuJoe]

8 hours ago, Sakkura said:

VR headsets do not have DPI, they have PPI. And it's not like PPI is more important than total resolution. What ultimately matters is the angular resolution, which depends on more than just the PPI or the total resolution.

Resolution absolutely matters, and is no less important than pixel density. You can have situations where a low PPI but high total resolution looks better than a high PPI but modest total resolution.

 

For example, a 4K monitor will typically look a lot sharper than the panels in a VR headset, even though the latter has higher PPI.

 

(for comparison, an Oculus Rift has a PPI of 456, while a 27-inch 4K monitor has a PPI of 163; it would have to be less than a 10-inch monitor to match the Rift's PPI)

Oops, I meant PPI. Not sure where I got DPI from. All I know is that the reason I can barely read the text in a VR headset is because of the PPI.

Edited November 25, 2018 by KuJoe
I was informed that DPI and PPI are the same thing. The more you know!

[Sakkura]

42 minutes ago, KuJoe said:

Oops, I meant PPI. Not sure where I got DPI from. All I know is that the reason I can barely read the text in a VR headset is because of the PPI.

Well, kind of. It's the combination of the PPI and how much of your field of view it fills. The VR headset has the panel really close to the eye and a lens that stretches it across a wide swath of your field of view, making the perceived resolution low. Otherwise the raw PPI is actually very good - the Oculus Rift has about the same PPI as the iPhone XS for example.