A short, light picture (5)

I believe the answer is:

photo

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'picture' is the definition.
(a photograph)

I cannot understand how the remainder of the clue works.

(Other definitions for photo that I've seen before include "In brief, a snapshot" , "Pic (abbr)" , "This race finish is very close" , "Snap, picture" , "Snap (abbrev.)" .)

I've seen this clue in the Evening Standard.

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