How many metering modes are there and for what scenes are they good for?
Matrix: Matrix metering uses very sophisticated and complex algorithms to predict the scene you are shooting and the correct exposure for that scene. The camera splits the scene up into a matrix and then takes a light reading on each individual segment. The exposure is based on different variables across the scene. We recommend using this mode in most scenes. This mode is good for evenly and moderately lit environments such as when shooting scenery and portraits with front-lighting.
Spot: Under spot metering mode, the camera only measure a very small area (usually 1.5% of the view) to get the most proper exposure. This mode is good for for partially lit environment such as around a stage, or for backlighting silhouette and advertis-ing photography.
Center: This mode is a classic metering mode for portrait shooting where the subject is in the middle of the viewfinder.