David Pogue's Digital Photography: The Missing Manual

Flash On or Off?

Ah, the flash. If ever there was a photographic function that not enough people consider, this is it.

You can understand why it's there, of course. Cameras love light. Light is everything to a photograph: It provides the color, sharpness, and shadow.

And if there's not enough light for a decent exposure, well, by golly, your camera stands ready to provide that light all by itself.

What most people don't consider, though, is that the flash generally provides horrible light. It's harsh, it's white, it's direct, and it comes from a single point: your camera.

The results are usually nothing like what you're seeing with your eye. If you're close to the subject, the flash can blow out the picture, giving your best friend a ghost face that looks like it was photographed during a nuclear test. Worse, the flash illuminates only about the first 10 feet of the scene; everything beyond that comes out black.

The flash on small cameras can also produce redeye, the disturbing phenomenon where your dearly beloved's pupils turn red like the devil's (see Notes on Redeye). And forget trying to take pictures through glass—at aquariums, in art museums, and through windows. Most of the time, you wind up with nothing but a big white splash of flash reflection. Enjoy, for example, this once-in-a-lifetime glimpse of the rare Estonian bifurcated snout shark:

To make matters worse, most consumer ...