Sigma DP2s review

The main reason SLRs take vastly superior photos to most compacts is because their sensors have around five times the surface area of most compacts. This also makes them much bulkier, though.

The Sigma DP1 was the first camera to cram an SLR-size sensor into a compact body with the DP2s the fourth instalment in the series. Although the SLR-compact hybrid market is now blooming, there’s still nothing else quite like these Sigma cameras.

The DP2s’s sensor records images at just 4.6 megapixels, but each pixel is measured in full colour. In conventional sensor designs, each photosite measures only red, green or blue light, and the data is extrapolated to produce a full-colour image (see [a hef=”www.foveon.com”]www.foveon.com[/a] for more details). The upshot is that the DP2s’s photos are small but breathtakingly sharp.

This large sensor has two other key benefits: low noise and a shallow depth of field. The latter throws backgrounds into soft focus, drawing attention to the subject, so is ideal for portraits. The lens, which has a fixed 41mm focal length, is well suited to portrait work, too, although its f/2.8 aperture isn’t as bright as we would have hoped.

Noise levels were lower than from any conventional compact camera, but not as low as SLRs manage. At ISO 400 shots were extremely smooth, but we had to switch to RAW mode and process in software to keep the quality up at ISO 800. At higher ISO 1600 and 3200 settings (only available in RAW mode) the results were good but not outstanding. A lack of optical stabilisation doesn’t help.

The DP2s won’t please those expecting SLR performance, either. It’s faster than its predecessor, but takes almost five seconds to switch on and shoot, while needing up to two seconds to focus is slow even by compact standards. The controls are rudimentary for such an expensive camera and the 320 x 240 video resolution is hopelessly low.

The DP2s is a beautifully conceived package, but at this price it’s impossible to avoid comparisons with Panasonic’s GF1 and Olympus’s Pen series. These cameras are better in low light, have more reliable automatic modes, are much more responsive and have interchangeable lenses. For all its virtues, the DP2s seems awkward and inflexible in comparison.