This mode breaks a scene up into chunks, each of which are measured independently. And then, after a microsecond of thought juggling such factors as where the focus point is and whether you’re shooting a landscape or a portrait, works out what the correct exposure should be. Well…usually. There are one or two situations where a camera lightmeter gets things spectacularly wrong. Unfortunately, although lightmeters are astonishingly clever they can also be incredibly dumb.
Light meters can be a the downfall of us all. Funny enough, Light meters are always messing up or are generally of no-use. Unless you know how to use them right and how you can tweek them to your personal style.