In photography, backscatter (also called near-camera reflection) is an optical phenomenon resulting in typically circular artifacts on an image, due to the camera’s flash being reflected from unfocused motes of dust, water droplets, or other particles in the air or water. It is especially common with modern compact and ultra-compact digital cameras.
Caused by the backscatter of light by unfocused particles, these artifacts are also sometimes called orbs, referring to a common paranormal claim. Some appear with trails, suggesting motion.
