Ring flash
A flash lighting system that illuminates the subject evenly and eliminates shadows by employing a circular flash tube that is mounted to the front of the lens. Macro photography is one of the most common applications for ring flash; nevertheless, it is also occasionally employed in portrait photography and other types of photography. When employed for the purpose of portraiture, the bigger ring flashes that are available for use in studios produce catch lights in the shape of a doughnut.
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