Originally Posted by Draconius

You don't really want to keep it on shutter priority unless you are looking to do pan-shots or time stop shots. You actually wanted to keep it on Manual so that you can change it all. Remember the camera meters the whole shot (unless you have it on another setting), and it meters with greys not whites in mind. I usually am 1 line beyond 0 in my camera. (-,,,.,,,0,,,.,,,+)