Andy Westlake tries out an unusual compact camera with a fixed ultra-wideangle lens in his Sigma dp0 Quattro review.
Sigma dp0 Quattro review – Noise
At low ISO sensitivities the dp0 gives exceptionally clean, detailed images. But things start to go wrong at higher settings, and JPEGs are practically unusable at ISOs of 1,600 and above. Raw images aren’t so bad, but they show exceptionally high luminance noise. ISO 6,400 is very poor indeed, with visible banding and colour blotching.