National Geographic photographer Jim Richardson took his iPhone 5s to Scotland and, after taking 4,000 photographs, called the camera on the device "very capable" with pictures that "didn’t look like I was having to settle for second best because it was a mobile phone".

Apple's Phil Schiller tweeted a link to the article this evening, commenting "iPhoneography".

With intense use (I’ve made about 4,000 pictures in the last four days) I’ve discovered that the iPhone 5S is a very capable camera. The color and exposures are amazingly good, the HDR exposure feature does a stunningly good job in touch situations, the panorama feature is nothing short of amazing—seeing a panorama sweeping across the screen in real time is just intoxicating. Best of all it shoots square pictures natively, a real plus for me since I wanted to shoot for Instagram posting. Once I figured out what the camera could do well I began to forget all the things it couldn’t do at all.

While the iPhone 5s still uses an 8-megapixel camera, it utilizes a sensor that has a 15 percent larger surface area, which means it will produce higher quality photos in low-light conditions. It also has a 5-element lens with an aperture of f/2.2, an improvement over the iPhone 5's f/2.4 aperture and the pixels are larger, at 1.5 microns, for better light absorption. All in all, the iPhone 5s has a 33 percent increase in light sensitivity.

Interested readers can follow Jim Richardson's Instagram page at @jimrichardsonng or #proofscotland from the Instagram iOS app. The full post from National Geographic's Proof blog has more images as well.