The essential element of this project is a Canon Digital Camera. It needs to be a Canon, unless your camera has a built in feature that will allow you to take pictures at a preset interval. I don know that many cameras on the market actually have this built in, perhaps some of the hi-end cameras do. For my project I used a Canon Powershot A550. Its several years old buy still very good for what I needed. It only has a 4x optical zoom and since I am far away from the object I am taking pictures off, it would be nice if I could get my hands on a camera with about 10x optical zoom - Canon SX1 IS or SX2 IS would be nice.
One other feature that your camera should have and that is the ability to run on an external power supply and be able to run continuously. I have disabled the LCD screen though.