Using an External Flash
Some cameras have a hot shoe into which you
can slip a dedicated flash unit.
Click to explore how a flash head can pivot up and down and rotate for bounce flash.
Flash photography has come a long way since the 19th century when a photographer had to ignite a tray filled with flash powder to illuminate a scene. Almost every digital camera comes with a small built-in automatic flash that is tied into the autoexposure system. This flash is convenient, however its range is very short and so close to the lens that photos of people often capture them with red eyes. It also emits a hard, direct light and can't be rotated to bounce flash off a wall or ceiling to soften it.
For better flash photography you need an external flash that slips into a hot shoe on top of the camera, or connects to the camera with a bracket and flash cord that plugs into a flash sync terminal on the camera. (There are also slave units that have a sensor so they fire when the built-in flash fires). If the flash is designed specifically for your camera it's called a "dedicated" flash unit, and the camera controls both the internal and external flash. Flash units not designed to work with the camera usually fire at full-strength unless they have their own output control.
One of the biggest advantages of an external flash is that you can swivel and rotate the flash head to bounce light off walls and ceilings.
Bounce flash can evenly illuminate a
scene that has depth because it spreads the light more evenly front to back.
When using an external flash you can use it alone or combine it with the builtin
flash for even more lighting possibilities.
Some cameras let you use the built-in flash and an external flash at the same time. Here these two flash units were used to take a "portrait". The flash from the front was created by the built-in flash. That from the side or top was created when the head of the external flash was rotated or swiveled to bounce flash off the wall or ceiling.