Lighting something close up is often difficult. Shadows can appear on the subject being photographed, particularly when using traditional flashes.
Special flashes, known as ring flashes, provide very even frontal illumination of subjects.
Ring flashes typically consist of two parts connected by a cord: a shoe-mount unit that fits on a camera’s hot-shoe and a circular-shaped flash that mounts in front of a lens. The flash mounts either directly or with a step-up ring.
Ring flashes are designed to work with both 35mm film and digital single lens reflex cameras. Some are fully dedicated for through-the-lens auto exposure systems. Some can be used wirelessly.
Quality ring flashes are expensive. However, they are ideal for illuminating medical and scientific subjects, or any close-up subjects where capturing fine detail is desired, such as photographing coin and stamp collections.