We’ve all taken photos of someone outside or in front of a window, only to find out, later, that the person’s face came out so dark that we can’t see it. To sum it up, the issue comes down to this: Some more-sophisticated cameras can detect and compensate for backlighting. But, if the camera thinks that the backlight is lit ‘normally’, it will underexpose the rest.
There are three easy ways to deal with this problem:
1) Use a flash to fill-in the subject. Many digicams allow you to force the flash on for exactly this situation. Keep in mind the range of your flash. If you’re shooting outdoors with the subject’s back to the sun, you may need to be pretty close to the subject for your flash to ‘fill’ the subject’s face.
2) If your camera offers it, is to switch to a ‘spot exposure’ mode. Using this mode, you can expose for the subject and ignore the back lighting. Depending on your gear, you may switch to this mode, put the subject in the center, and hold down an ‘exposure lock’ button while you adjust your composition. Or, you may need to switch the camera into a manual mode.
3) Use exposure compensation. Today, even some very basic cameras allow you to alter the exposure. For example, you may set exposure compensation to ‘+2’, telling the camera to expose two stops higher than it normally would. The advantage of digital photography is that you can take the shot, see how it worked out, and then adjust further if required.