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Apple's iPhone 5 may have sold millions, but it does have its share of flaws. One that has drawn a lot of attention is the so-called "purple haze" seen in photos when a bright light source is just out of frame. But is it really just the iPhone 5 that has this issue? Tests suggest otherwise.
Before anything, let's diagnose the problem. A number of suggestions have been floated by owners and commenters:
Oversensitivity to infrared light. No, although the shade of purple will be familiar to people who have encountered this problem: some cameras fail to filter out IR light, which overloads the sensor and blows out parts of the image. But not just on the edges, as seen?on the iPhone.
Sapphire glass lens cover. Nope: we might think of sapphires as being colorful ? blue and purple in particular, as?the gems certainly can be. But the synthetic?sapphire used as a scratch-resistant element is extremely transparent even well?outside?the visible spectrum of light.
Chromatic aberration or "fringing." This term refers to visual artifacts found in some photos, where high-contrast details have a sort of halo or double image near?them, often of a bright purple color, usually resulting from certain wavelengths of light traveling through the lens differently from others. But the iPhone haze isn't restricted to small details or color reproduction.
No, the iPhone 5 haze is a common problem called?lens flare. Lenses, even tiny, cheap ones like those in phones, are extremely complicated optically, and it's a difficult task to make all the light in the scene go exactly where the lens maker wants it to.
A bright light outside of the lens's field of view can shine light at strange angles onto the entire surface of the lens, and sometimes that light ends up being refracted inwards along with the light from the scene. The result can be anything from the colorful, geometric shapes we all recognize?to a total washing out of contrast and color.
Good lenses minimize lens flare by special coatings, complicated optical structures, and other mechanisms. But smaller lenses without room for such measures and lenses manufactured to lowers?standards will often exhibit dramatic and sometimes destructive flare ? as on the iPhone 5.
An?epidemic?of flaws or of complaints?
Anecdotal reports have built the lens flare problem on the iPhone 5 into an epidemic ? but careful testing done recently by both Consumer Reports and DPReview showed that while the iPhone 5 does exhibit plenty of lens flare, it's not alone.
The iPhone 4S showed about the same level of flare in both sites' tests, though other comparisons on the net have found it to be less. Consumer Reports also compared the iPhone 5 with a Galaxy S III, and found they both produced similar flare ? brightness, purple tint, and all.
Why so many reports from the Apple community, then? Consider that the iPhone has always been a more popular platform for photography, and more people use it to put photos online than other phones. Flickr's camera tracker has always shown the iPhone above well-known?canons from Canon, Nikon, and others, and of the top 5 phone cameras, 4 are iPhones. It's not a perfect measure, but it gives an idea of how popular the device is.
It makes sense that a very popular new product that is used more frequently for photography than its competitors would produce a ton of complaints. And of course once a person sees it, they go out and try it, putting the sun just out of frame and getting that now-familiar haze.
Apple's customer service acknowledged the issue, however, calling it "normal behavior." And the fact is that it is normal behavior ? for a bad lens.
Regardless of how many megapixels the camera has, its?low light sensitivity, the sophistication of the software, and so on, the most important aspect of the camera is the lens. And even the best phones out there have bad lenses when you compare them to almost any lens for an SLR camera. The cramped dimensions of the tiny?camera enclosure in phones mean there isn't room for the big, high-quality glass elements that go into good lenses. So you end up with lens flare.
Apple: The problem is behind the camera
The official solution is "Moving the camera slightly to change the position at which the bright light is entering the lens, or shielding the lens with your hand." This reminded some of Steve Jobs' famous remark regarding the so-called iPhone 4 "death grip": "just don't hold it that way."
But while there shouldn't be a wrong way to hold a phone in your hand, there is and has been for decades a right and a wrong way to frame a shot. Photographers and cinematographers have known for a century that positioning a bright light source just outside the frame will result in lens flare ? on some lenses more than others, but it?even happens on camera setups that cost half a million dollars.
It's up to the photographer to know their camera's shortcomings and?work around them. The iPhone 5 is no exception. Like most phones, it has a small, flare-prone lens,?and the framing of a shot should reflect that.
Do people have cause for complaint to Apple? It's possible that some phones may be afflicted more than others, just as some have arrived with dings to the finish or, in the past, yellow-tinted screens from still-wet glue. If some phones exhibit the flare significantly more than others due to a lower-quality run of lenses, that is a perfectly good reason to contact customer support and ask for a refund or replacement.
But if every unit shows more or less the same issue and in tests it appears similar to competing phones, then this is simply the result of taking the early-adopter risk of buying a device before such issues have been made known. Caveat emptor -- let the buyer beware.
Devin Coldewey is a contributing writer for NBC?News Digital. His personal website is?coldewey.cc.
Source: http://www.nbcnews.com/technology/gadgetbox/purple-haze-not-just-iphone-5-problem-1C6391778
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