updated 07:50 pm EDT, Mon October 24, 2011
iPhone 4S compared against its ancestors
A side-by-side comparison of iPhone camera quality by the co-developer of Camera+ (99 cents, App Store), Lisa Bettany, has shown the sheer improvement in the iPhone 4S camera quality compared to earlier models, dating back to 2007. The shots also show just how closely they compare against two frequent benchmarks for compact and DSLR cameras, the Canon S95 and EOS-5D Mark II.
The original and the iPhone 3G are visibly poorer in both a macro shot and an urban landscape as they both lack autofocus and have their focus and exposure locked together. Image quality sees the biggest leap in the iPhone 3GS, where autofocus starts working, but is still set back by low detail. The iPhone 4 brings in that detail and allows exposure and focus to work more separately, but also adds a bluish color cast for the macro shot and has issues with dark highlights.
The iPhone 4S is very close to the quality of the dedicated cameras, Bettany found. Although it's not as accurate as the 5D Mark II, it's much more comparable to the S95 and produces a more vivid but still balanced shot. Both shots carry a slightly yellow cast where the dedicated cameras are more neutral.
Similar leaps can be found in the histories of other companies where camera phones have grown in importance, such Samsung's attention to the Galaxy S II or to Sony Ericsson's Xperia arc and Xperia neo, both of which use the same Sony sensor as Apple. The contrast still shows the shift in technology and how much Apple's priority has shifted towards photography in four years. The iPhone 4S achieves its results through a back-illuminated CMOS sensor and a wider f2.4 aperture that together let in more light, a fifth lens element, and support for features such as autofocus lock and autoexposure lock, the last two of which are usually only present in pro or semi-pro cameras.
Apple once considered the camera a secondary feature and was well behind phones like the Nokia N95 but gradually began taking it seriously, most of all once it could start recording video and gained third-party app support. The iPhone 4 is now Flickr's most popular camera of any kind and is now thought to be beating most smartphones and some regular compact cameras.
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