Why do raindrops appear hexagonal on camera lenses? © iStock

Why do raindrops appear hexagonal on camera lenses?

You need to know a bit about the bokeh to answer this question.

Asked by: Richard O’Neill, Glasgow

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It’s a manifestation of an optical phenomenon called ‘bokeh’, which is Japanese for the effect of camera equipment on out-of-focus images. In the case of raindrops, it’s a result of the blades of the camera diaphragm creating a polygonal-shaped aperture. The exact shape varies on the vintage and type of the camera.


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