Some thoughts on the iPhone 5s camera
For many people in this section of the forums, the most important announcement yesterday was, without any doubt, the iPhone5s' new camera.
In the past months, we've seen some of the competition's attempts to catch up on what is arguably the most popular P&S today. Samsung upped the MP count to 13 on the GS4, Nokia stunned with the 41MP PureView, Motorola invented the somewhat controversial ClearPixel and HTC coined the term UltraPixel, sacrificing MP count in favour of larger pixels. Also, OIS was broadly introduced among flagship smarthphones.
So let's have a look at the new iPhone's camera specs:
The sensor size grew by 15%, which really isn't much. For comparaison: a 35mm FF sensor is more than 2.3x larger compared to APS-C. A MFT sensor is almost twice the size of a 1" sensor (Nikon CX, Sony RX100), but 40% smaller than APS-C. From that perspective, a 15% increase is good, but nothing to get really excited about.
Apple chose to stay at 8MP resolution. Not much to argue about that. 8MP are more than sufficient for everyday photography.
Sensor noise reduction was addressed by increasing the size of every pixel from 1.4 µm to 1.5µm. Again, a notable attempt, but not groundbreaking either.
Lens system / focal length
On their Sept.10 product presentation, Apple was very vocal about their completely redesigned lens system for iPhone 5s. Of course, Apple could not possibly have kept the same lens of its previous generation phone, since the larger sensor would have meant a shift in focal length. Most notably, it's faster (f/2.2 down from f/2.4).
The focal length itself is presumably unchanged at 33mm (equiv.). Personally, I would have preferred a wider one, something between 28 (my personal favourite) and 31mm (equiv.). When it comes to square crops (I'm looking at you, Instagram), a wider focal length comes in very handy. Also, landscapes do look a lot nicer.
Apple created an interesting solution with the use of a combined, dual flash system. While I would argue that one must avoid using (a fixed) flash at any cost, it's one of the more exciting features. Real-world use should give us a hint about how and to what degree this approach leads to better exposures.
iOS 7 comes with a new camera UI, and from what I've seen, it looks good. In order to avoid too much confusion among 'normal' people, Apple didn't try to introduce pro features to it's simple and pretty basic camera app. That's a good thing. For those looking for more granular controls, there are plenty of pro camera apps to choose from in the app store.
IS is handled through software only, combinig multiple exposures in a sort of 'best shot' mode. There is no mention of optical IS.
Video capture gets a new 120fps slow-motion mode, but limited to 720p.
Reading through the specs, one must conclude that the iPhone 5s' camera is a decent upgrade to its predecessor. It carries a slightly larger sensor with slightly larger pixels, a faster, arguably better lens, a redesigned dual flash and some added features on the software side. From that perspective, Apple did its homework and did it rather well.
The biggest problem with this camera is that Apple didn't address the most pressing issue its predecessors already had. Low light pictures will still be horribly noisy and blurry. The sensor and pixel size increase do not make up for the inexplicable lack of OIS. Software IS is nothing more than a gimmick.
Don't get me wrong: I do believe one can shoot (very) nice pictures with the iPhone 5s' camera, but I am absolutely conviced that the very minor improvements in IQ under given light conditions simply can't justify the (expensive) upgrade. The good news is: you can buy an iPhone 4S for cheap. In its price segment (free on contract or $450 off-contract), it's the only smartphone that shoots good pictures.