Labs

Digital cameras

When it comes to digital cameras, we take a very different approach to our normal tests. There are no benchmarks we can run to generate a performance result so we evaluate each camera by taking a selection of photos in controlled conditions on a tripod, as well as some more general-purpose shots without the stability of a tripod - the kind most people take in real life. We try to use the cameras in a wide range of situations, from bright outdoor conditions to dark indoor shots.

We also employ all the functions available on the cameras to get a good idea of their flexibility and usability. We use the advanced photographic controls on the £300+ cameras to assess their ranges and usefulness. Most of the cameras include continuous shooting and movie modes, but a stills camera is mainly used to shoot single stills, so we concentrate on this area in our tests.

Indoor photos

We take three indoor shots in the confines of our photography studio, which is used for most of the product shots in PC Pro. The main scene is set up to include differing textures, strong primary colours, blacks and whites, reflective items and both large and small text. The shot is framed identically for each camera and taken with both forced and suppressed flash. Where available, we use manual and tungsten white balances to account for the lighting used.

We also take an indoor shot using the camera's macro mode. This is composed of a bank note with some coins and a ruler, for measuring the area captured. We set each camera on the tripod to be exactly square against the desk to enable us to accurately detect any barrel distortion in the image.

outdoor photos

We take the outdoor shots from the roof of the PC Pro offices, which overlook London's West End and include landmarks like Centre Point and the Millennium Eye.

The direct sunlight and huge depth of field stress the camera's light metering, focus and exposure settings. We take two shots here - a wide landscape scene and a close-up portrait, the latter to primarily test skin tones. Many thanks to our very own Claire Kearney for offering to be our model for the day.

The ever-changing lighting conditions outdoors means the sky looks different in every shot (for details, and the photos, see overleaf).

What we look for

After uploading the images onto our usual test rigs, we scrutinise them for issues like barrel distortion, colour fringing and tonal range. We use two 19in Iiyama Vision Master Pro 454 monitors placed side-by-side rather than printing images out. Although this still doesn't guarantee perfect colour accuracy, it offers the best real-world solution.

We also look for specifics in each shot. The indoor shot without flash is checked for general colour accuracy, resolution and errors such as noise and compression artefacts. The shot with flash is checked for the spread and range of the flash and again for colour balance errors.

We calculate the area covered in the macro shot and check focus across the image, particularly in the corners. The outdoor photos are examined for accurate skin tones, exposure, colour and detail capture. We concentrate on the model's hair in the portrait shot for resolution, which gives a good indication of a camera's overall ability to capture fine detail.

Comparing cameras

Due to the wide price range and functionality of the cameras on test, they're split into two groups. The first includes cameras up to £300, and the second those costing over £300. This means that we compare like with like as much as possible, but the scores at the bottom of each review aren't comparable between the two groups. However, you can compare all the cameras' image quality in the quality graphs (see p81).

Since there are two distinct groups, we test each in a slightly different way when taking the shots described above. The cameras in the lower price bracket have all functions set to auto, as this reflects the point-and-shoot nature in which the majority of people will want to use them. With the more expensive cameras, however, we make use of their advanced functions to obtain the best possible pictures. For example, we used focus and exposure locks as well as shutter and aperture priority modes.

Many thanks to Belkin (www.belkin.co.uk, 0800 2235 5460) for providing a USB Memory Stick reader, SanDisk (www.sandisk. co.uk) for providing a USB CompactFlash reader and Cruzer USB SD/MMC card reader, and Crucial (www.crucial.com/uk, 0800 013 0330) for providing a 128MB MMC card.