1. Resolution
This is the number of pixels making up the image. With higher resolutions, you will be able to see greater detail and print larger pictures. So the more, the better. But not always:
- Compact and bridge cameras: once you go beyond 10 million pixels, the increase in quality is minimal (lens quality is rarely a key feature of these cameras). The resulting pictures will lack detail, sharpness and contrast.
- SLRs: higher resolutions are necessary for printing your pictures in large formats.
- At 20x30cm, 8 megapixels is sufficient,
- At 30x45cm, 10 megapixels is advisable,
- At 40x60cm, 12 megapixels or more will be needed.
2. Autofocus
Used to focus on a particular subject.
- Compact and bridge models: autofocus is fairly fast if the subject is well lit, but can be extremely slow in low light conditions (in which case, activating your camera's autofocus "assist light" if available will improve performance). Some cameras have an automatic face detection feature which can be extremely useful for focusing on the faces of the people being photographed, whether on their own or in small groups.
- SLRs: generally quite fast, but almost instant if your lenses have an ultrasonic motor. Continuous autofocus allows you to track a moving subject.
3. Burst mode
This is a key feature for taking action shots or sports pictures, or when taking pictures of your children..
- Compacts: fairly modest burst speeds, often fewer than 3 images per second.
- SLRs: up to 10 images per second.
- Shooting in burst mode can be combined with continuous autofocus: track a moving subject to ensure that most of the pictures remain sharp.
4. Optical stabilisers
When shooting freehand with shutter speeds slower than 1/60s, some motion blur is inevitable! Using an optical stabiliser, you will get a sharp image at speeds as low as 1/15s.
- Is your camera or lens labelled IS, OS, Power OIS, VR or VC (depending on the manufacturer)? This means it has a stabiliser!
Note
Forget about models offering digital stabilisers that increase ISO sensitivity, designed to give faster shutter speeds: the resulting pictures will be lower in quality.
5. Video
Video is definitely a feature that is on the rise, with more and more compacts, bridge models and SLRs offering it, whether at VGA or Full HD quality.
- Remember to purchase a high capacity memory card (at least 8GB) and extra batteries (shooting video uses a lot of power).
- With SLRs, various accessories will be required to achieve high quality video: snoot, shoulder mount, large viewing screen etc.
- Decide whether you want to shoot stills or video, but don't try to do both: you're likely to end up with neither!
6. Some of the latest features...
Here is a round-up of some recent innovations (some of which will no doubt be superseded before too long...):
- 3D, using a stereo lens.
- Waterproof or shock-resistant compacts.
- Compacts with interchangeable lenses: with external or electronic viewfinders, and prices equivalent to entry-level SLRs.
- Built-in projector: allows you to view your photos with groups of friends by projecting them on to a wall or ceiling. Around 1h battery life, though this is enough to view a fair number of pictures.