I have been reading a lot of books on photography. The latest of which is about "correct exposure". It went over making sure you take into account the ISO (essentially film quality), F/stop (essentially the apparent size), and the shutter speed (essentially what it sounds like). A lot of what he said I already knew some of I didn't but it had more to do with shooting with film (the things I didn't know that is). All the same I took it all to heart and it basically came down to I need to spend more time with my camera.
Point of all the rambling: the best way to get to know your camera is to spend time with it just like a person.
Picture one is F/8, ISO 100, and shutter speed of 300 (on a Nikon D300)
Same "exposure" but now it is a F/1.4, ISO 100, Shutter speed of 1000
(The huge difference if focus. The first being a broad focus and the second being a very small focus.)