A huge shift in the digital camera market has taken place over the last few years, namely the move away from traditional compacts and DSLRs and instead on compact system cameras (CSC).This has made it even harder to decide which digital camera to choose.

The principle of many CSCs is the same, with the benefits of relatively large sensors and interchangeable lenses of SLRS married with the portable form of advanced compact cameras. There are a handful of variations to this concept, but all are designed to deliver a high standard of functionality and image quality in a small and relatively inexpensive body.

Manufacturers have cited a number of target markets for this new breed of camera, from first-time users demanding an inexpensive way of attaining high-quality results, right through to enthusiasts who may tire of lugging around an SLR body and collection of lenses for a day's shooting.

The appeal to both audiences (and others) is clear, but are these really the best option for everyone? And where does this leave the alternatives? The following guide looks at what digital camera is right for your specific needs.

Compact cameras

Compact cameras have been traditionally targeted at less demanding, occasional users. Replete with 'smart' and 'intelligent' technology, many compact cameras are ideal for those happy to leave all the decision making to the camera rather than themselves. Ironically, these cameras can often be the most difficult to choose between, given that there are hundreds of models from a number of manufacturers.

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Pixels

Models priced below £250 all share a similar size of sensor, which today incorporates around 12-16million pixels (Mp). This comfortably meets and exceeds the requirements of most users.

While a greater number of pixels can be beneficial in good light, this can otherwise have a detrimental effect on image quality, particularly when you venture up a camera's sensitivity range to its four-figure ISO settings.

This doesn't mean you should actively avoid digital cameras with the most megapixels, but that your decision making should involve a number of other factors.

If you do plan on buying a simple compact camera, and you're likely to be using it in a range of lighting conditions, look out for those which use a backlit sensor, as these tend to capture images with less grainy and destructive noise, and with a wider dynamic range. It's possible to find these at a range of prices, from entry-level models under £150 to more advanced cameras twice as expensive, and the use of this technology is rapidly proliferating.

What lens?

Other things to look out for include the range of the camera's lens, as this will determine how suitable it is for different subjects.

A wideangle lens which begins at around 24 or 28mm, for example, is an excellent choice for indoor shots and landscapes, and those which extend to 250mm and beyond are ideal for nature and wherever you need to focus on far-off details.

If possible, look for cameras with either lens- or sensor-based image stabilization systems, particularly if you're looking to buy a camera with a relatively long zoom. These help maintain a higher standard of image quality than sensitivity- and processing-based technologies.

Viewfinder

Most budget compact cameras don't offer a viewfinder, although some manufactured by Canon and Sony still do. These are linked to the optical zooms of the cameras so that they move in tandem with the lens, and can be useful for shooting in bright light when LCD screens become hard to view.

Optical viewfinders are also found on higher-end compacts such as Canon's G12 and Nikon's P7000, although the majority don't have one at all.

Pushing the boat out

So, what if you have a little more money to spend - what camera should you be looking for then? And what are their benefits?

A more expensive compact camera may provide a larger sensor and a better quality optic, which together help improve all aspects of image quality. Many also offer manual control over exposure for when you want to get creative, and you may also get a raw shooting mode which will give you a better starting point for any processing you may wish to carry out yourself.

Furthermore, such models are likely to have a superior LCD screen to those on cheaper cameras, which will not only resolve details with greater clarity but will also be easier to view in harsh and sunny conditions.

Alternatively, if it's a large zoom range you're after, you may want to consider a bridge or superzoom camera. These combine expansive optical zooms with manual exposure options, which together provide control similar (but not equivalent) to that of a DSLR.

Alongside their LCD screens bridge cameras tend to incorporate electronic viewfinders with around 230,000 dots of resolution, although the performance of these varies wildly between models so it's worth investigating this before deciding on any particular model (assuming you'll want to use it).

These viewfinders also have the benefit of displaying much of the information found on the camera's LCD screen, which allows you to view and change settings without you needing to pull the camera away from your eye.

While the results from a bridge camera generally fall short of SLR quality, what you lose in quality you make up for with portability and the convenience of such a wide zoom range in a small and inexpensive body. Many now offer articulated LCD screens and HD video recording, and some even go on to offer a raw shooting mode.

Compact and bridge camera summary

In summary, if you have about £300-£400 to spend, and you want something pocketable yet capable, look out for a model with a healthy range of manual control, an LCD screen with at least 460,000 dots and ideally a backlit sensor. But before you do that, consider whether you'd be better off with a compact system camera instead.