Review: Nokia 808 PureView
Performance and Image Quality
In use, the 808 PureView behaves much like a conventional cameraphone, purely because of its form factor. If you're used to a phone like Apple's iPhone 4S, or any recent high-end Android offering, you won't have any difficulty adjusting to the 808.
A dedicated focus/shutter button on the right side of the phone (with the screen held in the orienation shown below) acts as a shortcut to activate the camera app even when the phone is sleeping. A 'hard' press is required to open the app and wake the phone - a quick or light press will be ignored, preventing accidental operation of the camera. From sleep to image capture is roughly 2-3 seconds depending on AF acquisition time, which isn't bad at all. Unlike a lot of other smartphones with 'hard' shutter buttons, the 808's shutter release has a two-stage movement, which allows for half-pressing to focus before taking a picture.
|The 808's camera controls are well thought-out and easy to access. A 'hard' button on the upper right side of the phone (when viewed in the orientation shown here) acts as a shutter button in the conventional way - half-press for focus, full press to take a picture. An on-screen shutter release is also available - it's the aperture blades icon in the centre right of the screen in this image.
In 'Creative' mode, (shown here) you'll see a panel along the left of the screen that provides access to key modes and features including ISO sensitivity, white balance and exposure compensation. Adjusting these settings is a simple matter of scrolling and selecting by touch, but we wish the icons were a little less obscure.
With the camera app running, autofocus performance is roughly in line with my expectations from a modern compact camera - a bit of hunting in low-contrast situations, but in normal shooting conditions the 808 focusses in less than a second (usually), and almost always with unerring accuracy. Unexpectedly, the only times I had real issues with focus were when shooting pictures of people, when the face detection would very occasionally just give me a blurry image for no obvious reason. The 808's metering system is similarly, very reliable, although the match between live view brightness and final exposure can be pretty wide in especially dark and bright conditions. I've found that it's best to bracket around a little in very bright light to be sure of getting a pleasant exposure. An on-screen histogram would help a lot, but although a histogram appears when you're dialing in exposure compensation, it vanishes again when that screen is dismissed.
Shutter lag is effectively non-existent once focus has been acquired. In poor light the 808's built-in AF illuminator kicks in and does a good job of providing enough light for focusing, but in this situation focus slows to usually at least a second for accurate acquisition.
In full 38MP mode, there's a pause of roughly three seconds after taking a photograph and being able to view it or take another one. In the reduced resolution 3/5/8MP modes this delay is much shorter - roughly one second, for 8MP files. Viewing captured images is quick and easy. Like most modern smartphones, the 808 allows you to flip through captured images by swiping the screen, and double-tapping magnifies the view for critical analysis of detail and focus accuracy.
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.
Full Resolution (38/36MP)
Let's start by looking at the big numbers - the 808's full resolution 38/36MP (depending on the aspect ratio) capture mode.
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.
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 spoke to a Nokia representative about this, and it seems 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.