Catch lights

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Catch lights are the 'sparkles' in the eyes which are often considered to be desirable in portrait photographs. Each light source capable of reflecting from the eye to the camera will produce a catch light. Catch lights will appear clear only when the eyes are well focused, and are one of the ways in which the viewer determines whether the eye appears focused or not. Therefore, adding catch lights in postprocessing may give an impression of sharpness in an otherwise blurred image.

A flashgun mounted on the camera is often used to achieve catchlights when the lighting conditions would otherwise not favour them.