What is bokeh?

Bokeh is a term you’ll often hear about in photography in relation to lenses. It comes from the Japanese language, and translates literally as ‘blur’. Bokeh is the name given to the aesthetic quality of the out-of-focus areas in an image, seen in the background as blurred circles of light. When parts of the foreground and background are outside a lens’ depth of field, the light that reflects from elements in those areas is rendered as circles. The points of light aren’t focused to a precise point at the image plane, so they become out of focus.