Flash synchronization is the method of coordinating the timing of a flash with the camera's shutter so that the flash illuminates the scene at the moment the shutter is fully open. Proper synchronization ensures that the image is evenly exposed and avoids partially lit or darkened areas caused by mistimed flashes.
Most cameras offer two flash synchronization settings: X and M. The X setting is used for electronic flashes, which fire instantly, while the M setting is for expendable flash types, such as flash bulbs, which require a brief delay before the shutter opens to allow the flash to reach full brightness. Understanding flash synchronization is essential for both studio and field photography, particularly when precise lighting and exposure are critical.