What to Check Before You Buy a Digital SLR
1. Viewfinder brightness: All DSLRs have optical finders that let you view through the lens, but they're not created equal in terms of brightness. If you often shoot in dimly lit interiors or at night, a bright viewfinder is essential. When comparing brands and models, make sure the lenses on the cameras are the same type and speed (f/stop) so you can make a valid comparison.
2. Handling and ergonomics: Make sure the DSLR you select fits comfortably in your hands and feels well balanced when fitted with the lens you'll be using most often. The shutter release should fall naturally under your index finger, and the most-often-used controls should be easy to reach and logically arranged.
3. LCD screen: Your DSLR's LCD screen should be large enough so you can easily check picture sharpness and composition. Helpful features to look for: a convenient magnifying feature that lets you zoom in on details, and a control that lets you increase LCD brightness so you can see the screen more easily in bright light or outdoors.
4. Shooting speed: Virtually all current DSLRs provide fast start-up and very short shutter lag times, but their framing rates differ. If you shoot lots of sports action, wildlife or kids at play, the ability to shoot at 3 to 5 frames per second is a real asset. If you specialize in landscapes, architecture, or adult portraits, blazing speed is less important.
5. Battery capacity: Most DSLR shooters use high-capacity memory cards (1GB to 8GB) so they can take lots of hi-res pictures without downloading, so battery capacity is crucial. Read the specs to compare the number of shots you can take per charge. Bonuses: cameras that can run on replaceable AA cells or accept enhanced-capacity packs.