How to choose a digital camera

The quality of a digital camera is mainly defined by four quantities: resolution, lens aperture, lens zoom range, lens quality, and software. CCD sensitivity also varies somewhat.

Resolution

Nearly all digital cameras use CCD's as the sensing element. This is what takes the place of film. The resolution is the number of pixels in the captured image. Computer images are divided into little dots called pixels. The more pixels, the more detailed the image can be. Here is a guide to choosing resolution, estimating the size print you can make from each:

1.3 Megapixel = 1280x960: Great 4x6's, acceptable 5x7's.
2 Megapixel = 1600x1200: Pretty good 8x10's.
3 Megapixel = 2048x1536: Great 8x10's, good 11x14's.
4 Megapixel = 2272 x 1704: Great 11x14's, and acceptable 16x20's.
5 Megapixel = 2560x1920: Pretty good 16x20's.
6 - 10 Megapixels = At this point you are usually limited by the lens, not the pixels.
Casual photographers are satisfied with bigger prints from each size, while those who like to look at 8x10's from a distance of three inches think I am being too generous in the above evaluations.