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iPhone 4's "Retina Display" Claims Challenged
adeelarshad82 writes "Of the many things that buyers might need to know about the new iPhone, Raymond Soneira — president of DisplayMate Technolgies — added one more to the list. Soneira challenged Apple's claims that Apple's new iPhone contains a so-called 'retina display.' According to Soneira, the resolution of the retina is in angular measure, 50 cycles per degree, where a cycle is a line pair, which is two pixels, so the angular resolution of the eye is 0.6 arc minutes per pixel. So, if you hold an iPhone at the typical 12 inches from your eyes, that works out to 477 pixels per inch. At 8 inches it's 716 ppi. You have to hold iPhone 4 out about 18 inches before it falls to 318 ppi. So the iPhone has significantly lower resolution than the retina."
Who cares about a ritnawhatchumacallit. If i get an Iphone I'll get laid! :D
$action = empty(PHP) ? backToC() : unset(PHP) ; "when the concrete cases are understood, the abstractions are readily
I'm not sure how discriminating your taste is, or what your preference is, and I assume you're male...
You are aware of what kind of person would be laying you because of your iPhone, right?
I mean, they probably wouldn't be nerdy *AT ALL*. What good is that?
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
Android OS is not actually an operating system by or for Androids.
Windows 7 wasn't really the idea of some random people in cafes and showers.
Saturns - not actually made on Saturn. Surprising, I know.
The Emotion Engine has never shed a single tear.
Magic Markers have no magical properties.
getting screwed != getting laid
My boss just walked by my desk and saw me holding a 12" drafting scale and cell phone to my forehead. Thank you slashdot.
It's about publishing, not anatomy. This argument is like saying we should have celebrated the millenium in 2001.
Jobs said "300 dpi is a magic number" and indeed it is. He is referring to an ancient publishing standard. In print publishing, 300 dpi is "laser quality". It is very common for a graphic artist to create a "print" version of an artwork at 300 dpi and an "online" version at 72 dpi (effectively zero, or "resolution unknown", or 1:1 pixel ratio). We have looked forward to 300 dpi screens for many years because then you just make one 300 dpi version for both print and screen. The most important number on the dpi resolution ruler is 300. It is extremely significant to ship the first 300+ dpi screen.
A similar magic number in audio is 20kHz, the generally accepted upper limit of human hearing and the standard for "CD audio". The CD was significant because it passed the 20kHz magic number, and consumer audio still uses that frequency range today, 30 years later.
The key thing with these magic numbers is that below them you get dramatically lower quality but above them you get severely limited returns. 300 dpi and 20kHz are the points where it takes an expert to tell the difference between them and a higher quality. Most people can tell the difference between 200 and 300 dpi, but most people cannot tell te difference between 300 dpi and 600 dpi.
So the author of this article should have done some publishing industry research, some graphic arts research, instead of researching the eye. That is what Steve Jobs talks about when he says Apple is not just technology but also liberal arts, a broader knowledge of the world than just science.
This article is not just ignorant, it's also mean-spirited, small-minded. Like people who say "Think Different" is bad grammar. It's poetry you fuck. Broaden your horizons.
Hopefully female :)
In soviet Russia, God creates you!
Nerd chicks dig wealth as much as any other kind. Yes, it's unfair.
Also remember, the colour resolution of the eye is far poorer than the b&w resolution of the eye, and the aim here is about colour.
I'm not entirely sure what you mean, but the fovea responsible for your "high resolution" sight contains almost exclusively cones, which are colour sensitive. Most of them detect red and green light, so the resolution in monochromatic red or green isn't that far below white light.
The rod cells on the other hand can only distinguish between black and white, but they are much sparser giving significantly lower resolution. (Their advantage is that they are extremely light sensitive, almost down to detecting a single photon. This is why you have no colour vision when it is dark. Another interesting consequence is that you are blind in the center of your visual field when light conditions are bad, since the fovea lacks rods.)
What does that translate to in terms of halftone printing? There's a world of difference between 90000 dye-sublimation continuous tones per square inch, and 90000 little squares that can be exactly black, cyan, magenta, or yellow. That's one reason why a "300dpi" magazine like Playboy still looks richer and better than the 1200dpi output of a color laser printer, and why an inkjet printer almost always produces better-looking continuous-tone images (ie, photos) than any laser printer. A 1200dpi color laser printer uses most of its resolution to get better interpolation. An inkjet printer that sprays magenta ink over yellow ink produces a muddy orange as long as the yellow ink is still wet. A laser printer that prints magenta over yellow will end up with... magenta. Likewise, a true laser printer can (in theory, at least) do more with 300dpi than a "LED" laser-like printer, because the laser's brightness and beam diameter can be modulated a bit, so you can simulate real halftone patterns a bit more easily. In contrast, a LED laser-like printer is going to charge rectangular areas of constant dimension, so your resolution is literally *it*.
It's kind of like trying to argue about the true resolution of a recent-vintage DLP light engine. In the old days, a DLP TV with 1280x720 resolution literally had 1280 x 720 little micromirrors on the DMD (well, more for overscan purposes, but it was basically a 1:1 correlation between a single micromirror and a single rendered pixel on the screen). Then, someone (Samsung?) figured out that if you used a brighter light and modulated their movement at a higher rate, you could use one mirror to illuminate a pair of adjacent pixels. Then the whole definition of native DLP resolution kind of went to hell, because nobody knew what a pixel of resolution on a DLP TV meant anymore.
If you really want to get depressed, try shopping for a HD video camera that's more than a hundred bucks, but less than $10k. There's a huge gray area in between, and the liberties that some manufacturers (not necessarily the lowest-end Chinese imports, either) take with their advertised resolutions is borderline fraudulent. There are cameras with interlaced sensor modules that claim to be progressive by virtue of double-buffering a pair of fields internally and outputting them sequentially. There are cameras that alternate the sensors red-green-blue-green-red-green-..., then count a red-green pair as one pixel, and the adjacent blue-green pair as another pixel (hey! instant resolution-doubling makes the marketing department happy). It's sad, but in 2010 we're still reduced to taking digital photographs of black and white angled lines and using the same metric people had to use a hundred years ago for lack of a better way to describe camera resolution. 10 years ago, if you bought a camera with 1280x960 resolution, you knew damn straight it had 1280 clusters of red, blue, and green sensors horizontally, and 960 of 'em vertically. New cameras, alleged to have near-gigapixel resolution, commit frauds that basically amount to counting the number of discrete sensors sensitive to any wavelength of light, then play games with interpolation algorithms to see just how high they can claim their resolution is without getting indicted by state attorneys' offices for false advertising.
What does that translate to in terms of halftone printing? There's a world of difference between 90000 dye-sublimation continuous tones per square inch, and 90000 little squares that can be exactly black, cyan, magenta, or yellow. That's one reason why a "300dpi" magazine like Playboy still looks richer and better than the 1200dpi output of a color laser printer...
If you're actually interested:
"300dpi" is something of an oversimplification. Images are sent down at 300dpi. The printing plates are usually imaged by laser at 2400dpi, but each halftone cell takes up more then one "dot". Print resolution is measured in "lines per inch", and ranges from ~85 lpi for newsprint to over 200 lpi for higher end printing. I'd guess that playboy prints much closer to the 200lpi end of the spectrum.
A "1200" dpi inkjet (usually more like 1440dpi) will be able to print 1440 dots per inch, but multiple dots are needed to make each halftone cell. In effect, even the best consumer level inkjets are half the resolution of an offset press.
As for laser printers, if you look at the industrial level digital presses (many of which are really glorified laser printers), they produce print that is much closer to the level of an offset press, but then again they can cost well into the six figures, so I guess you get what you pay for.
Apple has never claimed not to be evil, they're just very stylish about it.