The super zooms do have a few things going for them. The light weight, small bulk and price, for a start. The lenses are not only versatile, they are also generally good. Canon use their own lenses, Sony use Zeiss and Panasonic use Leica optics. Kodak brand their lenses as Schneider of Kreuznach to appeal to those old enough to remember the excellent Retina range of film cameras. Kreuznach seems to have relocated to China, but never mind.

How do they do it for the price? In part it is because of the size of the sensor in a digital camera. A 35mm film frame is 36mm by 24mm. A typical sensor in a compact digital camera, including the super zooms, will be around 6mm by 4mm (sizes vary from camera to camera). A digital single lens reflex may have a typical sensor size of 24mm by 16mm. The most expensive digital SLRs have sensors the same dimensions as a 35mm film.

The compact camera sensor is tiny which has benefits and costs. Because of the small area that has to be illuminated by the lens the optics can be smaller and therefore cheaper. Depth of field is greater with the smaller sensor which makes focussing slightly less critical. In fact one of the most frequent complaints from super zoom owners is that the depth of field is too great. It can be difficult or impossible to produce a picture with an attractive out-of-focus background.

The tiny sensor produces another unwanted side effect -- picture noise. This is the grainy effect generated by the sensor when too many photo-receptors are set too close together. The larger sensors in SLRs are less prone to picture noise because of the greater pixel size and pitch. The Nikon D70 SLR has six million pixels on an area approximately 24 by 16mm. The Canon S3IS super zoom also has six million pixels but on an area 6 by 4mm. The Canon S3 produces nice pictures but the Nikon D70 does better.

Where the single lens reflex triumphs over any other type of camera is in the viewfinder. Electronic viewfinders give a crude representation of the subject, rather like looking at a small portion of a TV screen close-up and through a magnifying glass. These EVFs are low resolution affairs that do not give enough information to judge focus and tonal distribution. A good single lens reflex connects the photographer directly with the subject.

When it comes to responsiveness there is no contest. Compact superzooms have improved over the past couple of years but they still feel squishy compared with the instantaneous response to the shutter button that you get with an SLR.

Bottom line: the ideal kit consists of a digital single lens reflex and enough lenses to reach from 24mm to 300mm, plus a compact digital camera such as the excellent Canon Ixus 800is or the Sony Cybershot DSCW100 for those times when portability is needed or an SLR might look a bit pretentious. Imaging speaks from desire, not from experience!

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