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A Professional Perspective On Apple's Retina Display
Reader BWJones, who is a retinal scientist, sends in this detailed analysis of the iPhone 4's "retinal display," which includes photomicrographs of the display pixels of earlier generations of iPhone as well as the iPad. Well worth a read. "... as you can see from these images of the displays I captured under a microscope, the pixels are not square. Rather they are rectangular, and while the short axis is 78 microns, the long axis on the iPhone 4 pixel is somewhere in the neighborhood of 102 microns. ... While [an earlier analysis by] Dr. Soneira was partially correct with respect to the retina, Apple's Retina Display adequately represents the resolution at which images fall upon our retina. ... [I] find Apple's claims stand up to what the human eye can perceive."
Why would dell? they don't make electronics. They build computers byu assembling other peoples electronics.
I have submitted stories about real ground breaking technologies from:
Intel
Giga-Byte
Nasa
Chevy
IBM
MS.
and many, many others. I stop submitting 2 years ago because I had not had a submission accepted since 99.
Now, I don't mind the apple stories. It's not like this is a limited space newspaper.
BTW that tech isn't as ground breaking as you seem to think. It's like there isn't much there in regard to new tech, so people are glomming onto and straws they can grasp to justify waiting hour to buy a product that they could walk in and buy in 2 weeks. Hell it might even be fixed by then.
The Kruger Dunning explains most post on
As someone that used to work for an agency:
300 DPI represents an reasonable economics tradeoff between accuracy and cost. You can have 1270 DPI (professional photo typesetters run that high), but how much do you want to pay for it? Those machines are $500k+. And yes, your eye can tell the difference between 300 DPI and 1270 DPI.
Artwork developed by print agencies is done at 300 DPI and no higher because of limitations on file transfer size and professional printer RIP speed. Trust me, if an 8" x 10" photo could be squashed into 3-5MB and rasterized in a short amount of time at 1270 DPI, there would be printing equipment and printers offering that as a service overnight.
Finally, standard 35mm film is around 10,000 DPI, dude.
Hmmm, I also used to and *currently* work in the print industry. I don't have time to explain the relationship between DPI and LPI when it comes to reproducing halftones in print, plus the effects of the only three different kinds of printing technology (ink based, toner based, and ink jet based) *and* the effect that has on different kinds of paper stock.
Essentially, the "sweet spot" for color halftones is 340 dpi when you have the option of a very high linescreen with very low dot gain. There's sort of a formula for dpi, which is 2.5 X the linescreen (LPI); but it cannot be followed exactly if you're worried about tracking and other quality issues. 300 dpi is a nice round number that makes for "easy" to email files as well as a good standard for target resampling in PDFs and the like. Anything higher than 300/340 dpi and you'll have to have an LPI so high in order to prevent banding you can't keep the dots on the page (again, depending on which printing technolgoy you use). If you're LPI is too low it looks like the old newspaper photos, and also runs the risk of rosetta morie patterns being visible if the angle of the 4 inks (if using only 4 inks) isn't adjusted properly.
For toner and ink jet based printing, it's easier to get away with as little as 150 dpi for color photos since the LPI is moot at a certain point where dot gain and near continuous tone transfer of pigment is possible.
For greyscale halftones, you usually want 600 dpi for SWOP printing; again, it's not forumulaic, since that high of resolution may or may not result in banding depending on the LPI and the distance-to-amount of gradiation.
For black and white, such as text, you want the dpi to be as high as your output dpi - so you don't see any of the jagged edges between the points of black and the white of the paper underneath.
Finally, standard 35mm film is around 3,200 dpi depending on the emulsion chemistry.
It's impressive, but it isn't super impressive. The Toshiba Portege G900 already had a screen at 313ppi, and Sony Erickson X1 is 312ppi.
What makes it newsworthy, is Jobs said (I paraphrase) "It's as good as the human eye can perceive." That's why he named it the "retina display".
A scientist with a Ph.D. came along and called bullshit, saying that the human retina can perceive pixels much higher.
The Ph.D. in this article respectfully disagreed, and said the previous scientist:
A.) Used the wrong figure for retinal resolution when he made his calculations (0.5 arcminutes instead of the 0.78 arcminutes established by a recent, authoritative study) and
B.) Failed to factor in losses in the optics of the human eye regarding how much light will actually hit the retina.
With A fixed and B factored in, the scientist concludes that the practical limit of the human retina (what it can distinguished given the amount of light that hits it) is 286ppi when held at 1 foot away from the eye (the ideal distance for viewing detail). The iPhone is well above this, at 326ppi, which means Jobs was right, and the name is apt.
It's worth noting that there are quite a few phones that beat the 286ppi limitation, but the iPhone has the highest.
Basically it looks like we don't need any higher resolution than what the iPhone and others have achieved, anything more would be pointless.
That, to me, is very impressive.
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
No one hears frequencies that high. People that claim to do so are generally hearing much lower frequency harmonics of the sound that they claim to hear. The commonly quoted maximum human-audible frequency is around 24kHz. Secondly, 3840 X 2400 is the largest display resolution I could find any mention of (aside from multi-display arrangements). You could find a display with over 3x the pixel count of a 1080p display, but not with 3x the resoution. That's a 22-inch display by Toshiba, which means it's about 2/3 the dpi of the iPhone screen. Essentially, you shouldn't be able to see the pixels from over 2 feet away, 3 feet if you have excellent eyesight.
So....can I have your autograph, Kal-El?
It is pitch black. You are likely to be eaten by a grue.