We shoot a specially designed chart in carefully controlled conditions and the resulting images are analysed using DXO Analyzer software to generate the data to produce the graphs below.
A high signal to noise ratio (SNR) indicates a cleaner and better quality image.
For more more details on how to interpret our test data, check out our full explanation of our noise and dynamic range tests.
However, we suspect that this is a result of some of the other cameras' heavy-handed processing of images which removes noise at the expense of detail.
Cameraphones have very small sensors and if the pixel count is pushed too far this can reduce their ability to record tonal changes in the highlight and shadows. As a result bright areas of the sky in landscape images burn out while the shadows go a deep black because the camera has a low dynamic range.
This chart indicates that the Nokia Pureview 808 camera's JPEGs have at least a 0.5EV higher dynamic range than the other smartphones' cameras up to a sensitivity of ISO 200. Above this value it maintains a better dynamic range than the Samsung Galaxy S2 and Motorola XT720, but is overtaken by the HTC Evo 3D.
At ISO 1600 the Nokia Pureview 808 has a restricted dynamic range so highlights will be prone to burning out and shadow detail will be lost easily.