In a group of cameras this month that you might be hard-pressed to tell apart, the E-420 is a breath of fresh air. First of all, Olympus claims it’s the smallest and lightest DSLR there is. That isn’t quite true – its predecessor the E-410 was marginally smaller, but we’re splitting hairs. This is certainly the most compact current DSLR model around, weighing just 636g with kit lens and battery.

The E-420 uses the Four Thirds lens and sensor standard, developed by Olympus and Kodak. Four Thirds cameras have a significantly smaller sensor than the standard APS-C type. That means lenses can be smaller for the equivalent focal length. Hence the E-420 comes with a Zuiko 14-42mm kit lens, which gives the same 28-80mm or so of other stock lenses, but is more compact.

There’s a downside to a smaller sensor, though. Smaller, denser pixels mean increased image noise. This does make itself felt at sensitivities above ISO 400 – the results from the Canons in particular are far cleaner – but below that it’s less of an issue. One thing we didn’t like, though, was the results when shooting in JPEG mode: shots were over-processed and lost significant detail.

On the features front, you get 10 megapixels, live-view mode and CCD-shift sensor cleaning. The only modern feature missing – both from the body and stock lens – is image stabilisation.

Beyond its size, the E-420 has some endearing features. Its styling is a little retro, complete with old-style d-shackles on the body for attaching the strap, rather than the simple metal loops fixed into the body of other cameras. Menu operation is simple – it’s more akin to a GUI than a standard set of menu lists, making it easy to adjust everything from ISO to colour space from a single options screen.

Not only that, but there’s no sign of Olympus limiting the E-420 just to differentiate from expensive models. You get spot metering with two different choices of spot size, plus exposure bracketing. Its maximum burst rate is 3.5fps, which is equalled only by the Canon EOS 450D. The only drawback is a lack of a depth-of-field preview using the viewfinder, but you do get the facility in live-view mode.

Ultimately, the all-conquering Sony A200 means it loses out on an award this month, but the E-420 is a brave design that has a lot going for it.