On the surface, the Pentax K20D is not unlike the K10D. Under the skin, though, it's very different.

The biggest change is the swap to a 14.6-megapixel CMOS sensor. It's clear by now that you don't get a lot more definition with these higher pixel counts, but every little helps and it does mean that fine detail is resolved with a little more subtlety.

A sophisticated SLR

High pixel counts are often associated with higher noise, but this doesn't appear to trouble Pentax because the K20D goes right up to a maximum ISO of 6400.

It should be ideal for fans of low-light photography, then, and all the more so with Pentax's improved Shake Reduction (SR) system, which claims it can shoot at shutter speeds four stops slower before risking camera shake.

This system moves the sensor to counter camera movement, where Canon and Nikon systems put the stabilisation mechanism in the lenses. The advantage of the Pentax system is that it can be used with any current lens.

It's sophisticated, too - the sensor is moved with magnets rather than motors, and in three dimensions rather than two. The camera even uses focal length data from the lens to fine-tune its reactions.

Nifty dust removal function

Other noteworthy features include a basic Live View mode, pixel mapping (to identify and blot out any dead pixels), a dynamic range enlargement feature to cut down on blown highlights and a Dust Alert function to check for sensor dust.

This works very well. To activate the function, just point the camera at a white surface and press the shutter release. The camera then displays a white field with any dust spots clearly delineated.

If you find any (we did) you can activate the camera's dust removal process (we did) and then check to see if the dust has gone (it had). It's a simple and obvious system that works well.

The resolution and the advanced features make this camera ideal for keen enthusiasts looking to step up from a simpler, 'starter' SLR. Indeed, the K20D is part of an expandable, professionally-orientated system.

There's an optional battery grip and the ability to swap focusing screens to better suit particular styles and types of photography.