FINALLY finished reading this thread (over the course of a few weeks).
I know it's been discussed several times in here, but does someone have a good, in-depth explanation of ISO? I understand Aperture and Shutter Speed, but ISO doesn't make much sense to me. And how do you know when to use which ISO? I guess I understand low #'s for daylight and high #'s for indoor/night. But what about cloudy days, bright rooms, etc.? Is it just something you need to fool around with until it looks right?
Also, a little help on the exposure compensation (+/- spectrum looking thing). Is this basically just a tool to quickly change the exposure without having to change all the settings?