Image Quality: Full Resolution (38/36MP) 

The 808 is a perfectly pleasant phone to use for taking pictures - it has more options than most, and handles reasonably well as a camera. Where it really shines though is image quality. The 808 produces without a doubt the best quality images I have ever seen from a smartphone, and in some respects challenges a lot of 'proper' cameras, too.  

Let's start by looking at the big numbers - the 808's full resolution 38/36MP (depending on the aspect ratio) capture mode.

 At low ISO settings, in good light, the 808's full-resolution is excellent. Although not quite as detailed as we'd expect from a DSLR with a similar pixel count, the 808's JPEGs are very nice indeed.
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Being a cameraphone, it's easy to forget just how big the 808's sensor is. Although not nearly as large as the sensors in DSLRs or most mirrorless interchangeable lens cameras, it is big enough at the lens aperture setting of F2.4 to give a pleasant background blur when capturing subjects that are close to the camera.
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If you click through the images above to get to the full-sized original files you'll see that full resolution output from the 808 isn't just a 'stunt' setting. Resolution at low ISO sensitivity settings is genuinely very high, and in terms of detail, images from the camera at this setting can satisfy pretty critical requirements, including large prints. At 100%, low-contrast detail has a slightly 'digital' appearance, but to be honest, given that we're talking about a camera fitted inside a telephone it's hard to complain.

 PureView (3/5/8MP) 

As I said in the introduction to this article, the 808 PureView's maximum output resolution of 38MP is far from the full story when it comes to photography. Most of the time you're unlikely to need full resolution output from a smartphone camera, and I'd expect that most serious mobile photographers will probably keep the 808 in one of its three 'PureView' reduced resolution settings. In these modes, you get the benefit of Nokia's proprietary oversampling, but remember that this doesn't apply when you're fully 'zoomed in', at which point you are effectively just looking at a crop from the full-resolution 38MP capture.

This image was captured at ISO 64, in 8MP PureView mode. At 100%, detail is pin sharp, and resolution is truly impressive. You can count the blades of grass in the near foreground of this shot.
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Another 8MP shot, this time taken at ISO 400. Exposure is accurate and detail capture is again, very high. Some granularity is visible in the smooth tones of the sky at the top of this image but it's subtle.
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This image was taken in 5MP mode, with the 808 'zoomed' to the furthest possible extent to concentrate the composition on the tree branch in the foreground. This is a fairly low-contrast scene but detail capture is high.
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When light levels drop, most cellphone cameras struggle to keep shooting without flash. But the 808 PureView has a maximum ISO sensitivity of 1600, which makes it impressively versatile in marginal light. 

This shot was taken in the 808's 8MP PureView mode and at ISO 800, JPEG image quality is impressive - certainly comparable with high-end compact cameras at 100%. It's easy to forget that despite its small form-factor the 808 is packing a sensor much larger than most of them.
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This shot was taken very in low light, also at ISO 1600 at the long end of the 808's 'zoom' in 3MP PureView mode. Image quality isn't great, (there's no oversampling benefit at full 'zoom', remember) and there's some banding visible too, but overall I'd call this acceptable given the conditions.
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Highlight Clipping 

When examining my sample images from the 808, the only real indication that I was looking at pictures from a compact device is dynamic range - or rather the lack thereof. This is one of the very few black marks against the 808's camera, that in scenes with a moderately wide tonal range, if you expose for the midtones you will probably see some highlight clipping.

This scene, taken at the 808's full resolution of 38MP in the 4:3 aspect ratio, demonstrates the phone's most serious weakness as a camera: highlight clipping.
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The 808 has delivered a somewhat bright (but not overexposed) image of this lakeside scene, shot in 5MP PureView mode, and highlight clipping is very apparent.
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There's not much you can do about clipping, short of mounting the phone on a tripod and exposure bracketing (the 808 offers a 3/5 frame exposure bracketing feature of up to +/-4EV) or deliberately underexposing using exposure compensation, then pulling midtones up later using software. I have found that shooting in the 808's PureView modes improves dynamic range very slightly in real-world use, but clipped highlights are the 808's achilles heel at all of its four output resolutions.

Clipped highlights are a pretty common problem in images shot with cameraphones and compacts, and one that manufacturers are increasingly solving using dynamic range expansion and high dynamic range (HDR) modes. Unfortunately, the 808 PureView doesn't offer an equivalent feature. 

I was having trouble with clipping in the log in the foreground of this shot, so I took a bracketed burst of three images at 0.7EV intervals and blended them quickly in Photoshop. Although much less convenient than an in-camera HDR function, it has worked well.
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From conversations with representatives, we understand that Nokia tried to include an HDR feature in the 808, but ran into technical issues because of the huge processing bandwidth required to quickly capture then blend multiple 38MP exposures to create an HDR image. Bracketing was included in the 808's feature set to satisfy the needs of serious HDR enthusiasts who like to do their blending on a computer.