- Most camera companies tout their megapixels as the main feature for each model camera. Megapixels determine the resolution and quality of the image, so this is important but not necessarily as important as you might think. For example, once you are past 15 megapixels, there's really no difference you can see with the naked eye, and for most applications, 10 to 12 megapixels give high enough resolution to meet your needs. Once you settle on this range, you can narrow your search and look for other features.
- Most DSLRs use a charge-coupled device (CCD) digital imaging sensor that appears to magnify the image by 1.5. In other words, a 50mm normal lens---one that shows you through the camera an image the same size and perspective you would see with your eye---becomes a 75mm portrait lens, moving the image closer to the sensor. The newer full-frame DSLRs use a CCD that gives the same aspect as a film camera would, meaning a 50mm lens really is a normal lens. Since tests in magazines such as Popular Photography & Imaging show there is little difference in image quality between these, price will be a major deciding factor. Of course, if you want an 18mm wide-angle lens to really be 18mm, the full-frame camera gives you wider range for your images.
- Other features to look for include how big the viewing screen on the back of the camera is and whether it will show you live real-time images. Obviously, the bigger the screen, the better you will be able to see the image you just shot. Live images on the screen, a standard in low-end point-and-shoot cameras, generally are available only on higher-end DSLRs. Since you generally need to be looking through the viewfinder to compose your images and make the correct exposure settings, this live image feature may be superfluous. Another consideration is whether you already own a film or digital SLR and lenses for it. If you already have a Pentax system, going with a new Pentax camera will allow you to use the lenses you already have on the new camera. Switching to a Nikon will entail either buying all new lenses or getting adapter rings. Using adapter rings to mount one company's lenses on another company's camera works, but it generally means you will lose automatic features, including auto focus and auto aperture.
