A portrait taken in front of a window with a great view in the backgorund sounds like a good scenario for a great photograph. However, the contrast range between your subject and the background is likely to be too great for the sensor to handle. If the camera’s meter in influenced by the background, the subject will be too dark, maybe even a silhoutte. To get a correct exposure on the face you’ll need to take a selective light reading, though of course all the background detail will then be overexposed. The only way to balance the two is to increase the light level on the face (using either reflectors, or flash) to more closely match the background level.

Bracketing

Bracketing allows you to shoot additional exposures either side of your first reading, giving you a greater chance of obtaining an optimum exposure. The camera calculates the extra exposures based on your initial reading and by what increment you wish to bracket your shot by. It then takes a series of exposures at the different settings in quick succession.