Originally posted by Zealex I took a photo of my friends dog with the sun behind me. I used spot metering and the dog was properly exposed however the sky was completely blown out, the blinkies went off...
That's exactly what it's supposed to do.
Spot metering is typically used to get readings from several parts of the scene. First, you point it at the darkest spot you want to see detail in and note the meter reading. Then, you point it at the lightest spot you want to see detail in and note the reading. Then, you average the two readings to get the proper exposure. This is the most accurate method of metering. It's not always quite that simple, but you get the general idea.
Originally posted by Zealex Also, I was under the impression center metering was best because it properly exposes your subject correctly
Center-weighted metering reads the entire frame, but gives more weight (priority) to whatever is in the center. That's fine if the scene is not very contrasty (boring), and your subject is dead center (also boring). Most of the time, you're better off using matrix metering.
Matrix metering is like an automated version of spot metering. The camera takes a whole bunch of spot meter readings and feeds them into the on-board computer. The computer then looks in its database for a match. It then knows that you're taking a picture of, say, a landscape. So, it brings down the exposure to avoid blowing out the sky, but not low enough to drop the grass in the foreground into shadow. It's not perfect, but under 'normal' conditions, it does pretty well.