Sigma DP2 review

Of all the cameras that claim to deliver SLR quality from a compact body, Sigma's DP2 is arguably the most convincing. It's certainly the most unusual. It's a little larger than the average compact camera but smaller and lighter than Olympus's E-P1. However, its sensor is only fractionally smaller than most SLR sensors.

The sensor's size isn't its only unusual attribute. While every other sensor we've seen uses a colour filter array, this one has three sensors that are, in effect, layered on top of each other, capturing every pixel in full colour. The resulting images have a modest 4.6-megapixel resolution, but the detail captured is broadly on a par with that of 10-megapixel cameras.

Considering Sigma's expertise in lenses, the DP2's may seem surprisingly modest, with no zoom function and only an f/2.8 aperture. However, focusing light on to a big sensor with such a compact lens is a superb achievement. Focus was sharp into the corners of our test shots, with no chromatic aberrations or vignetting. Meanwhile, the large sensor produced a shallow depth of field, blurring backgrounds in a pleasing way that isn't possible with conventional compact cameras.

The large sensor didn't deliver the low-light image quality we'd hoped for. Photos at the top ISO 800 setting for JPEGs weren't bad but they weren't up to SLR standards, with noisy shadows and some magenta-coloured blotches. RAW shots processed in Adobe Lightroom looked better and allowed ISO speeds up to 3200, but still fell short of SLR standards.

This wasn't our only concern. The controls are reasonably laid out but the etched button labels were almost illegible. Performance was poor, taking six seconds to start and up to four seconds between shots. Worst of all, the autofocus was slow and unreliable in low light, and manual focus is tricky on the 2?in screen.

These flaws are disappointing, but the DP2 still makes an excellent carry-everywhere camera for carefully composed daylight shots.