Jobs claims the iPhone held at 12 inches from your face has pixels too small to be resolved by your eye. Soneira, the display expert quoted in the magazine articles, disputes that. He uses the 0.6 arcmin resolution for the human eye (so we use the scale factor = 5730). Let?s use that and run the numbers.
Strictly speaking, I think the presentation slide got the terms wrong, The slide at the presentation says 300 is the limit of the retina, when it should have been more specifically identified as an eye that can see 20/20. It sounds like Soneira was quoting retina numbers, and the figure used on the presentation should have been a little more specific on the whole eye system (the lens being the likely limiting factor), though they might have been trying to justify calling it a "Retina Display".
Repeat a few times to reduce the possibility of random guesses
Dr. Raymond Soneira should easily be able to count the missing pixels if what he contends is true.
I did something like that, 36" and 48" measured using a tape measure, from a 100ppi screen, making it roughly equivalent to 300 and 400ppi at 12". I could still see the dots at both distance, it was pushing it though on the farther distance. That still makes me more excited to try this screen. Hopefully it pushes the computer display industry to denser screens, and hopefully the OS makers can get off their collective asses and get resolution independence into prime time.
this is the first time i've heard of Soniera.. so I can't speak to his qualifications, but I know badastronomer is a really smart dude.
and by the way.. this really is waaaaay to much math to be doing to determine whether or not the screen looks good. I don't care what it says on paper.. does it look better than the one I have now? yes or no is all i need to know. I don't necessarily care how or why
So what does all this mean for the iPhone? First, here are the claims.
Jobs claims the iPhone held at 12 inches from your face has pixels too small to be resolved by your eye. Soneira, the display expert quoted in the magazine articles, disputes that. He uses the 0.6 arcmin resolution for the human eye (so we use the scale factor = 5730). Let?s use that and run the numbers.
Something 12 inches away means your eye can resolve dots that are bigger than
12 inches / 5730 = 0.0021 inches
So if the pixels on the iPhone are smaller than 0.0021 inches in size, then Jobs is right. Your eye won?t resolve them. If the pixels are bigger, Soneira is right, and your eye can resolve them.
The actual iPhone 4 has 326 pixels per inch (the display is 960 pixels high, and about 2.9 inches in length). You have to flip that to get the size of the pixel in inches:
1 / 326 = 0.0031 inches
Uh oh! Things look bad for Jobs. The iPhone pixels are too big! At one foot away, your eye can resolve the pixels, and Jobs must be lying!
Or is he? Remember, Soneira used the 0.6 arcmin resolution of the eye, but that?s for perfect eyesight. Most people don?t have perfect eyesight. I sure don?t. A better number for a typical person is more like 1 arcmin resolution, not 0.6. In fact, Wikipedia lists 20/20 vision as being 1 arcmin, so there you go.
If I use 1 arcminute instead, the scale factor is smaller, about 3438. So let?s convert that to inches to see how small a pixel the human eye can resolve at a distance of one foot:
12 inches / 3438 = 0.0035 inches
Aha! This means that to a more average eye, pixels smaller than this are unresolved. Since the iPhone?s pixels are 0.0031 inches on a side, it works! Jobs is actually correct.
[Note: in the articles about all this, they used units of pixels per inch, whereas I've used the size of the pixels themselves. You can flip all these numbers to convert. The iPhone4 has a resolution of 326 ppi (pixels per inch). Soleira says the eye can resolve 1 / 0.0021 = 477 ppi. However, normal vision can see at 1 / 0.0035 = 286 ppi. So the density of pixels in the iPhone 4 is safely higher than can be resolved by the normal eye, but lower than what can be resolved by someone with perfect vision.]
So, the scientist is using the best case scenario for calculation versus a normal case? Given what my wife, who is a researcher, tells me about scientific results in research are done, I am not surprised.
I don't know where you get that, that sounds like you're blowing smoke. I've had ordinary consumer scanners clearly resolve thousands of lines per inch, the fibers of the paper can look like logs. The best optical microscope can read down to 0.2 μm, I think that translates down to about 128,000dpi. Some types of lab equipment can detect atoms, which is far smaller.
Even a simple hand-held magnifier will show the dots in the iPhone 4's display. It doesn't require anything fancy.
However, few people read their iPhones with even a simple magnifier. With the unaided eye, it's either impossible (if you have 20/20 vision or worse) or difficult (if you have much better vision than average) to see the pixels.
who the heck holds their phone just 12" from their eye. 18-20 more likey, so IT IS A RETINA DISPLAY
Well, I hold my iPhone around 20 cm from my eyes. Around 8". 20" would be around half a meter - no way.
But of course, I'm myopic ... and before I had an operation for it I would have had to hold it 10 cm from my eyes unless I had my contact lenses on ...
BTW, holding an iPhone half a meter away - don't you get tired in your arms?
This is starting to be a common thing from Apple, the half truth.
It's like:
"Macs are safer than PCs". Well, this is because Mac is a minor platform, so crackers are no interested on making virus for Mac, not because Mac is really safer than PCs.
"iPad is the best device to surf the web". How can it be the best device when many webs can be seen correctly due to the lack of Flash support??
"iPad lasts a day long". Well, here Apple redefines how log is a day.
anyway, spoke to my dad the other day. He sounded fine. He was doing his walkibg rehab as he's still in the hospital.
Today he is moved to Winchester hospital ICU for yet another infection.
Guys. Girls. I just got married not to long ago. He has nit seen her as my wife or his daughter in law.
I am not working and have nit seen my family since 2004.
Please pray he gets well once and for all.
That he doesn't lose the rehab he put into it.
That he snd I can oneday go for a walk so I can tell him some things I've never told him and that this new joint venture I started that both two people want to be involved and that I can via GOD AND A MIRACLE get home to see my dad and family.
Thanks.
May it all come back to you. 100000000000 fold. Amen.
Some of you are missing the point entirely. People will be going to the Apple stores and and they will see a very nice display. They won't be counting pixels and measuring the distance. This geek trolling is really unnecessary.
Well, if we're actually going to take this pixel-picking click bait seriously...
"...18 inches from the eye, much farther than standard use for a mobile handset."
Curious, I picked up both my handheld and a tape measure, repeatedly, standing, sitting, walking... Invariably, I hold mine somewhere between 15"-22" from my face. Of course this is asinine, but good for a laugh. Try holding an object 12" from your eyes and reading 9 pt type.
Steve is the guy who claims that people hold the device 10 to 12 inches from the eye. You disputing him?
Those that have even worse eyesight hold it 12 inches from their eyes. Who is this "expert" anyway? Sounds like someone that needs a hug.
Steve is the one who made the 12 inch claim.
This expert is the one who showed that the iPhone touch sensor is more accurate than the touchscreens on any other popular cellphone. He's kind of a hero in the iPhone world.
Well, I decided I had to measure the resolution of my eyes myself, using the method on the wikipedia page mentioned above. I created two 1000 x 1000 images with one-pixel black lines, one horizontal and one vertical, using this simple Matlab script:
Code:
a = repmat([1 0],1000,500);
imwrite(a ,'lines_vertical.png')
imwrite(a','lines_horizontal.png')
I put the images on my 24 inch LED Cinema Display, and on my 15 inch Macbook Pro. I measured the distance I had to move my eyes away from the display to make the lines disappear. The results were the same for the horizontal and vertical lines (both devices have square pixels so the numbers are the same as wel), so I only put the results for the vertical lines (horizontal resolution) in the table.
I couldn't figure out how to make a table on the forum so the table is over here:
Make sure you put your viewer on "actual size" (in Preview.app this is command-0).
I also put the Matlab script and the spreadsheet (OpenOffice format) in the directory in the second link, so you can play with it.
It turns out that my eyes have a resolution of a little bit more than 0.6 arc minutes, using this test. The last column in the table gives the values for the iPhone 4. I used 304 mm, which is 12 inches, because that is what Steve Jobs said. This is 0.88 arc minutes, so I guess I will be able to see pixels when holding the iPhone4 at a 12" distance.
I tend to use my iPhone at a distance of between 300 and 500 mm, depending on what I'm doing. I guess it's still an awesome display btw.
Comments
Jobs claims the iPhone held at 12 inches from your face has pixels too small to be resolved by your eye. Soneira, the display expert quoted in the magazine articles, disputes that. He uses the 0.6 arcmin resolution for the human eye (so we use the scale factor = 5730). Let?s use that and run the numbers.
Strictly speaking, I think the presentation slide got the terms wrong, The slide at the presentation says 300 is the limit of the retina, when it should have been more specifically identified as an eye that can see 20/20. It sounds like Soneira was quoting retina numbers, and the figure used on the presentation should have been a little more specific on the whole eye system (the lens being the likely limiting factor), though they might have been trying to justify calling it a "Retina Display".
Display a 100x100 image on the screen.
Remove some pixels.
Repeat a few times to reduce the possibility of random guesses
Dr. Raymond Soneira should easily be able to count the missing pixels if what he contends is true.
who the heck holds their phone just 12" from their eye. 18-20 more likey, so IT IS A RETINA DISPLAY
Those that have even worse eyesight hold it 12 inches from their eyes. Who is this "expert" anyway? Sounds like someone that needs a hug.
Set up an iPhone 4 so it is viewed from 12".
Display a 100x100 image on the screen.
Remove some pixels.
Repeat a few times to reduce the possibility of random guesses
Dr. Raymond Soneira should easily be able to count the missing pixels if what he contends is true.
I did something like that, 36" and 48" measured using a tape measure, from a 100ppi screen, making it roughly equivalent to 300 and 400ppi at 12". I could still see the dots at both distance, it was pushing it though on the farther distance. That still makes me more excited to try this screen. Hopefully it pushes the computer display industry to denser screens, and hopefully the OS makers can get off their collective asses and get resolution independence into prime time.
this is the first time i've heard of Soniera.. so I can't speak to his qualifications, but I know badastronomer is a really smart dude.
and by the way.. this really is waaaaay to much math to be doing to determine whether or not the screen looks good. I don't care what it says on paper.. does it look better than the one I have now? yes or no is all i need to know. I don't necessarily care how or why
http://blogs.discovermagazine.com/ba...ne-resolution/
So what does all this mean for the iPhone? First, here are the claims.
Jobs claims the iPhone held at 12 inches from your face has pixels too small to be resolved by your eye. Soneira, the display expert quoted in the magazine articles, disputes that. He uses the 0.6 arcmin resolution for the human eye (so we use the scale factor = 5730). Let?s use that and run the numbers.
Something 12 inches away means your eye can resolve dots that are bigger than
12 inches / 5730 = 0.0021 inches
So if the pixels on the iPhone are smaller than 0.0021 inches in size, then Jobs is right. Your eye won?t resolve them. If the pixels are bigger, Soneira is right, and your eye can resolve them.
The actual iPhone 4 has 326 pixels per inch (the display is 960 pixels high, and about 2.9 inches in length). You have to flip that to get the size of the pixel in inches:
1 / 326 = 0.0031 inches
Uh oh! Things look bad for Jobs. The iPhone pixels are too big! At one foot away, your eye can resolve the pixels, and Jobs must be lying!
Or is he? Remember, Soneira used the 0.6 arcmin resolution of the eye, but that?s for perfect eyesight. Most people don?t have perfect eyesight. I sure don?t. A better number for a typical person is more like 1 arcmin resolution, not 0.6. In fact, Wikipedia lists 20/20 vision as being 1 arcmin, so there you go.
If I use 1 arcminute instead, the scale factor is smaller, about 3438. So let?s convert that to inches to see how small a pixel the human eye can resolve at a distance of one foot:
12 inches / 3438 = 0.0035 inches
Aha! This means that to a more average eye, pixels smaller than this are unresolved. Since the iPhone?s pixels are 0.0031 inches on a side, it works! Jobs is actually correct.
[Note: in the articles about all this, they used units of pixels per inch, whereas I've used the size of the pixels themselves. You can flip all these numbers to convert. The iPhone4 has a resolution of 326 ppi (pixels per inch). Soleira says the eye can resolve 1 / 0.0021 = 477 ppi. However, normal vision can see at 1 / 0.0035 = 286 ppi. So the density of pixels in the iPhone 4 is safely higher than can be resolved by the normal eye, but lower than what can be resolved by someone with perfect vision.]
So, the scientist is using the best case scenario for calculation versus a normal case? Given what my wife, who is a researcher, tells me about scientific results in research are done, I am not surprised.
I don't know where you get that, that sounds like you're blowing smoke. I've had ordinary consumer scanners clearly resolve thousands of lines per inch, the fibers of the paper can look like logs. The best optical microscope can read down to 0.2 μm, I think that translates down to about 128,000dpi. Some types of lab equipment can detect atoms, which is far smaller.
Even a simple hand-held magnifier will show the dots in the iPhone 4's display. It doesn't require anything fancy.
However, few people read their iPhones with even a simple magnifier. With the unaided eye, it's either impossible (if you have 20/20 vision or worse) or difficult (if you have much better vision than average) to see the pixels.
That's enough to say this is a great display.
who the heck holds their phone just 12" from their eye. 18-20 more likey, so IT IS A RETINA DISPLAY
Well, I hold my iPhone around 20 cm from my eyes. Around 8". 20" would be around half a meter - no way.
But of course, I'm myopic ... and before I had an operation for it I would have had to hold it 10 cm from my eyes unless I had my contact lenses on ...
BTW, holding an iPhone half a meter away - don't you get tired in your arms?
It's like:
"Macs are safer than PCs". Well, this is because Mac is a minor platform, so crackers are no interested on making virus for Mac, not because Mac is really safer than PCs.
"iPad is the best device to surf the web". How can it be the best device when many webs can be seen correctly due to the lack of Flash support??
"iPad lasts a day long". Well, here Apple redefines how log is a day.
And so on...
Yawn.
Nutrasweet causes temp. short term memory loss
French frys cause cancer
margerine is better for you
margerine is worse for you
don't sit too close to the tv
anyway, spoke to my dad the other day. He sounded fine. He was doing his walkibg rehab as he's still in the hospital.
Today he is moved to Winchester hospital ICU for yet another infection.
Guys. Girls. I just got married not to long ago. He has nit seen her as my wife or his daughter in law.
I am not working and have nit seen my family since 2004.
Please pray he gets well once and for all.
That he doesn't lose the rehab he put into it.
That he snd I can oneday go for a walk so I can tell him some things I've never told him and that this new joint venture I started that both two people want to be involved and that I can via GOD AND A MIRACLE get home to see my dad and family.
Thanks.
May it all come back to you. 100000000000 fold. Amen.
Apple gets nothing but hurt for creating the highest ppi for mobile devises,
Naw, they are getting hurt for spouting pseudo-scientific nonsensical claims.
At 366 dpi, only the very most acute instruments can detect the dots. In a lab.
Are you sure about that? I have used 600 dpi printers since the late 1980's, and I can easily see the dots with my naked eye.
Well, if we're actually going to take this pixel-picking click bait seriously...
"...18 inches from the eye, much farther than standard use for a mobile handset."
Curious, I picked up both my handheld and a tape measure, repeatedly, standing, sitting, walking... Invariably, I hold mine somewhere between 15"-22" from my face. Of course this is asinine, but good for a laugh. Try holding an object 12" from your eyes and reading 9 pt type.
Steve is the guy who claims that people hold the device 10 to 12 inches from the eye. You disputing him?
Dr. Raymond Soneira should easily be able to count the missing pixels if what he contends is true.
Easily? I don't think that conclusion is borne out by what he wrote.
Those that have even worse eyesight hold it 12 inches from their eyes. Who is this "expert" anyway? Sounds like someone that needs a hug.
Steve is the one who made the 12 inch claim.
This expert is the one who showed that the iPhone touch sensor is more accurate than the touchscreens on any other popular cellphone. He's kind of a hero in the iPhone world.
So we are in agreement that 326 ppi are smaller pixels than someone with 20/20 vision can differentiate at 12" away?
I don't think so.
"Soneira claims that the actual distinguishable resolution of the human retina is 477 ppi at a distance of 12 inches. "
ISTM that this is a matter of fact and not opinion.
Are you sure about that? I have used 600 dpi printers since the late 1980's, and I can easily see the dots with my naked eye.
You just lost all credibility. The dots from a 600dpi printer overlap. The individual dots are about twice the size of 1/600 in across.
I don't think so.
"Soneira claims that the actual distinguishable resolution of the human retina is 477 ppi at a distance of 12 inches. "
ISTM that this is a matter of fact and not opinion.
then it comes down to which expert's analysis one chooses to accept.
a = repmat([1 0],1000,500);
imwrite(a ,'lines_vertical.png')
imwrite(a','lines_horizontal.png')
I put the images on my 24 inch LED Cinema Display, and on my 15 inch Macbook Pro. I measured the distance I had to move my eyes away from the display to make the lines disappear. The results were the same for the horizontal and vertical lines (both devices have square pixels so the numbers are the same as wel), so I only put the results for the vertical lines (horizontal resolution) in the table.
I couldn't figure out how to make a table on the forum so the table is over here:
Eye resolution comparison table
You can download the images here and do the test for yourself:
http://tauserver.wtb.tue.nl/basd/pics/lines/
Make sure you put your viewer on "actual size" (in Preview.app this is command-0).
I also put the Matlab script and the spreadsheet (OpenOffice format) in the directory in the second link, so you can play with it.
It turns out that my eyes have a resolution of a little bit more than 0.6 arc minutes, using this test. The last column in the table gives the values for the iPhone 4. I used 304 mm, which is 12 inches, because that is what Steve Jobs said. This is 0.88 arc minutes, so I guess I will be able to see pixels when holding the iPhone4 at a 12" distance.
I tend to use my iPhone at a distance of between 300 and 500 mm, depending on what I'm doing. I guess it's still an awesome display btw.