Speedlight
A small, portable, battery-powered flash designed to sit on a camera's hot shoe or a light stand.
Measured in
GN (guide number)
In depth
Speedlights trade power for portability: a typical unit delivers perhaps a fiftieth of a studio head's energy but runs on four AA cells and fits in a pocket. Their zoom heads, tilt-and-swivel mounts and through-the-lens metering make them the default tool for event and location work, and several can be combined for a portable studio.
Examples in practice
Three speedlights on stands, triggered by radio, light a portrait in a hotel room with no mains power available.