> I mean, does anyone actually notice the difference?
Absolutely.
Absolutely.
Also, don't be a stranger.
LOL, didn't know my brother was on hackernews, too. What's up man!
Question: how do you type / swype with your device so close? I've just tried and my focus kept shifting from the back of my typing hand to the screen and back, very tiring.
As far as typing I hardly look at the screen then and ppi don't really matter then. If I am just checking my notifications it barely comes out of my pocket. But when we are in a discussion of ppi being useful, I assume we are talking about the uses where you are actually looking at the screen.
Edit: Just realized that when I type longer messages or emails I tend to hold it 2 handed landscape and hold it pretty close(around 1 foot away) and tap it out with my thumbs because I find it more accurate. So I guess that is how one would type with it that close.
Perhaps screen brightness also impacts this - do you run f.lux?
I think everyone saying "yes I see a difference" should be doing some double blind validation. I've had people tell me they could tell the difference between 720p and 1080p at 20 feet. That is physically impossible for the human eye.
- PPI/resolution
- Media quality/resolution
- Distance
- Panel quality/size
See: http://www.anandtech.com/show/7743/the-pixel-density-race-an...
My example of tv screen and resolution is geared more to this: http://carltonbale.com/1080p-does-matter/
Take an 80" 4k tv, you need to sit about 5 feet for an average human to see the difference.
I'd like to see equivalents for phones and dpi/screen size and distance.
Also 20/20 is not only not perfect vision, it's not even average [1]. So using that as the baseline is stupid, it's the low end not the high end.
Second the human eye does not have a fixed arc resolution, different specific detail scenarios have different degrees of accuracy. But if you're going to use this shortcut, you better go with a number on the upper end of things instead of the lower end, so more like .4 arcminute.
The net result is there is real, technical merit in going all the way up to 600 PPI assuming it's held 12 inches away. There's still arguably value to be had beyond that, but it starts getting more into just being a pointless spec war. Right now, though, we are very firmly well inside technical worth.
1: http://precision-vision.com/Introduction-to-Visual-Acuity-Me...
Well that would depend on the device. If it's a 5" phone, then yes, obviously. If it's a 21" display, also, yes. If it's a 75" TV, probably not.
Usually people that I see (myself included, I have a Nexus 5 and a Nexus 7), hold our devices at about half an arm's length. At that distance, the pixels are discernible, especially if one has better than 20/20 vision.
http://wolfcrow.com/blog/notes-by-dr-optoglass-the-resolutio...
A baby's vision is around 20/800 [1] (extremely poor).
[1] http://optometry.osu.edu/research/VisualPerceptionLaboratory...
On the Nexus 5 (440 dpi), I can't see them anymore.
Resolutions above this seem unnecessary to me -- but for the N6, 1080p would mean 360 dpi, so that might be sub-perfect. 1440p will be perfect for sure.
I can't see jaggedness on my iphone 4 at 'www' in the browser either, and that's at 326 PPI.
But fair enough. The low 400s range seems like a solid enough improvement. I just don't get the upper 400s like the Nexus 6's 493, and perhaps the 500 range next year. Obviously there's a bit of extra battery and a bit of extra processing hardware required for that, however small, I'd want to hang on to it beyond the low 400s PPI range.
[1] National Centre for Social Research and University College London. Department of Epidemiology and Public Health, Health Survey for England, 2001. 2nd Edition. Colchester, Essex: UK Data Archive, June 2004. SN: 4628.
[2] Global Eyeglasses Market (2005). Eyeglasses MCP-2532: A global strategic business report. Global Industry Analyst, April 2008.
http://precision-vision.com/Introduction-to-Visual-Acuity-Me...
That article has some interesting phrasing which I think is causing confusion. (For me at least.) It looks like they're using 'normal' to mean 'average in the range' some of the time and 'mean population visual acuity' other times. Mostly they're using the former. So 'normal vision' or 'average eyesight' refers to the range of 20/20 eyesight and not 'mean eyesight'. That doesn't explain that second sentence, though, which seems to go back to 'mean human visual acuity'.
At the very least, they could stand to revise the writing in that sentence. If they did mean to imply that the average person has 20/20 vision, I think they're going to have to provide a source. I did slightly more digging and I couldn't find any journal publications that list less than 60% of adults as having corrected vision. Either the remaining 40 have strongly superhuman vision or the number is off. I think there is at least one blind person (legally worse than 20/200) for every person with super human (20/10, the physical limit for humans) vision.
A simple numerical test based on that last point seems to illustrate the unlikeliness of a 20/20 average. To state again, 20/10 is the physical limit for human vision. Any higher and it's not physically possible to pack more photoreceptors into the retina or focus the pupil tighter. Bad (legally blind) vision is in the realm of 20/200. The National Federation for the Blind[1] shows there are roughly 6,700,000 blind Americans of all age groups. We will assume that they're exactly at the legal bound for blindness and not worse. To find how many superhumans we need to make the average 20/20, I think we can use (6700000200 + x10)/2 < 20 We need x to be less then -133999996. So it's simply impossible for the average vision to be 20/20.
It's still possible that number is correct and that the average American has 20/20, but at this point the majority of the scientific publications and formal surveys do not support the idea. If you can find additional sources (I'm so sorry to keep asking), please let me know.
I would recommend, for the sake of clarity, adding '20/20 corrected' or '20/20 rectified' to your original post. If I hear someone say, "I have 20/20 vision," my first thought is, "this person has perfect vision", not, "this person wears glasses."
I'll go back and add that clarification on my replies.
EDIT: It's too late to go back and edit my topmost comment. :(