For those of you buying digital cameras, most of you need to stop worrying about the number of megapixels among the various brands. Many people base their decision on this, and yet once you get above 3 megapixels, it is the least important factor. The number of megapixels dictate how big a print you can make, and anything over about 3 is fine for an 8x10. You might want to go to 5 if you want to make 11x14 prints. Anything over this, you need to be using a medium format camera -- because 11x14 and up is pretty much the threshold where you start seeing problems with various small format LENSES. Even the best of the small format lenses won't go to 16x20 without running into problems. In fact, if you are just making 8x10 prints, or looking at photos on your monitor, the number of megapixels (once you get above 3) is probably the LEAST important factor in determining how good the photo will be.

More important than the sheer number of megapixels a camera has are four other things:

(1) the QUALITY of the sensor. This would include how well it lines up the little dots that make up the various colors (whether you get what is called fringing), how much noise it produces, and how quickly it will overheat. ALL digital sensors will eventually overheat, but it is pretty obvious that if yours does it in 4 seconds, you're going to get problems that someone else, whose camera overheats in 30 seconds, won't have.

(2) the quality of the LENSES. This would determine things like chromatic aberration (where different colors of light fall on different places on the sensor or focus differently), it is the main factor in determining how sharp the image is, and etcetera.

(3) the quality of the peripheral electronics and of the mechanics. These can add noise (even to a camera with the best possible sensor), cause your zoom lenses to jam, and can cause many other very serious problems.

(4) The size of the photosites. This is a major factor in determining how efficient a sensor will be (bigger is better).

There are also two other things to look at: the camera's reputation for reliability and the manufacturer's reputation for servicing that particular camera are chief among them. Doesn't matter how good any particular piece of equipment is if it is in the shop and the service people are giving you the run-around.

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I am a trained professional. Don't try this at home.