I work with different departments depending on the shoot. I ask this because all the greats that I've read about started with being ACs. Tommy Upshaw Dear Tommy, I believe that either the electrical or the camera department are great training for becoming a cinematographer. The most important thing is observing and asking questions. Working on a film set you have many opportunities to watch the way a cinematographer uses the light, the choices he or she makes, the way they relate to the director and actors.
Observation is important.
Ask if you can see the dailies. However, I have seen tests from several laboratories and like the results. You will learn most by shooting a test yourself and speaking with the lab directly. This way you will discover what the technique can do for you, rather than relying on someone else's ideas. The American Cinematographer Magazine is probably the best source of printed material on this subject.