There’s a great article on Gizmodo today about how digital cameras collect photons in your digital camera.

The name of the game, as you’ve probably gathered by now, is collecting light. And in fact, the way a digital camera “sees” actually isn’t all that different from the way our eyeballs do, at one level. Light, which is made up of photons, enters through a lens, and hits the image sensor (that boring looking rectangle above) which converts it into an electrical signal, sorta like it enters through an eye’s lens and strikes the retina, where it’s also converted into an electrical signal.

This is more of an intro to the technology, and probably won’t help you decide whether to go with the Nikon or the Canon (check out for some great advice on that front), but there are some great diagrams and pretty good explanations. If you’re a real photo geek, this is probably overly simplified  – but I found it quite informative.