Last month, Canon suffered the ignominy of being displaced in the digital SLR category of our A List, after being our DSLR of choice for almost three years with the EOS 300D and latterly its successor the 350D. Hoping to snatch back the crown from Nikon’s superb D80, the 400D is Canon’s next consumer DSLR.

Any new camera has to have a megapixel rating to equal its peers, so the 400D is replete with a 10-megapixel sensor, up from the 8 megapixels of the 350D. That isn’t the only difference, though. It also addresses what’s becoming the Achilles heel of the DSLR: sensor-borne dust. The front element of the sensor is attached to a piezo-electric element, and every time the camera is switched off this vibrates for a couple of seconds in an attempt to shake off any particles. Assessing the system’s effectiveness is difficult, but if you’ve had to go through the nerve-wracking process of manually cleaning a sensor with an air blower, you’ll appreciate the help.

Among the other minor changes is the presence of a nine-point auto-focus system, borrowed from its big brother the EOS 30D. The 350D’s seven-point system was adequate but occasionally struggled; the newer system seems a little faster and more sure-footed in low light. And while the burst frame rate hasn’t increased beyond 3fps, the burst depth has been more than doubled from four RAW frames to 10, or up to 30 or so JPEG frames.

The body design is almost identical to that of the 350D, which means that the handgrip is smaller than that of most competitors. Some find this awkward, but we’ve found that if you adopt the standard method of holding the lens barrel with your left hand to take most of the weight, it ceases to be an issue. The only big physical change is at the back of the body, where the old 1.8in LCD monitor and secondary LCD settings display have been replaced by a single 2.5in screen. This means that all camera settings aside from the basic shooting mode — which is still selected by the top-mounted rotary control — are set via the colour display. To reduce the distraction of having a screen lit up underneath your nose, there’s a proximity sensor beneath the viewfinder that de-activates the screen when you put your eye to the camera.

This change has two consequences. First, it increases the sluggishness of operation due to the slight switch-on delay of the screen. Second, since the battery pack is the same as the 350D’s and the screen’s power-draining backlight will be on for more of the time, battery life is reduced. On the face of it this isn’t a problem, since the battery life of all Canon models these days is excellent, but it means that if you do start running low in the field you can’t de-activate the screen to save power. The upside is a larger monitor, but we’re not keen on the compromise.

Conventional wisdom has it that more megapixels equals more noise, and we were worried that in bowing to market demands for higher numbers, the basic image quality of the 400D would have decreased. Thankfully, that isn’t the case, and there’s no discernible difference in noise performance or image quality: it’s as excellent as ever. Even at ISO 1600, where noise is apparent, its quality is closer to film-grain luminance noise than the far more distracting chrominance noise that plagues lesser cameras. If you buy the standard kit with 18-55mm lens, which hasn’t changed from the 350D, the limiting factor is the quality of the lens itself, which tends to produce obvious chromatic aberrations. Replacing it with a higher-quality optic will pay dividends.

The trouble with the 400D is that, while it’s still a superb camera, it isn’t unequivocally better than the 350D. The removal of the secondary LCD and the need to set everything via the monitor is easy to see as a retrograde step, especially as the Nikon D80 has both the 2.5in LCD and a fantastically informative top-plate-mounted secondary LCD. The D80 is a real step forward for digital SLRs in the sub $2000 price bracket, giving you a dedicated exposure bracketing control, spot metering, sensitivity up to ISO 3200, the ISO Auto mode and an improved stock lens. The 400D offers none of these.

If you’re a 300D owner with a large investment in Canon EF lenses, or a first-time buyer on a tight budget, the 400D is a worthwhile purchase. But those with a 350D will be less impressed — while it’s a great camera in its own right, it’s much harder to recommend in the face of the superb D80.