Megapixels are considered one of the most important features of a camera, but this measure is not the only important factor that determines image quality. Megapixels only determine how large the resulting image can be based on the total number of pixels. What actually determines the quality of images captured by a camera is the type and quality of the image sensor. The sensor makes the difference between a good 10-megapixel picture and a bad one.

The megapixel count determines how large the image can be printed without a loss of quality. For example, a 1.3 megapixel cell phone camera can take images that are good for printing of up to 4x3 inches. If the image is blown up beyond that size, image quality degrades dramatically.