I'm trying to understand the practical differences between the metering options that are available. If my camera isn't auto-selecting the correct exposure settings that I need, my options as I understand them are a) adjust using exposure compensation, b) meter off-scene, use exposure lock and re-compose, or c) switch to a different metering mode (spot, partial, etc). So what are the pros and cons, and most practical? Seems like metering off-scene and using exposure lock is the easiest, because you can do it with your thumb without looking up from the viewfinder. I also read somewhere that some people leave exposure compensation set -1/3 stop all the time to protect against blown out highlights. Is this a practical suggestion?