point light source

Definition: (1) In photographic studio: small light source without reflectors or light shapers, used throw sharp shadows, also to place in confined spaces. (2) In dark-room: lamp with very small filament and no diffuser used to provide a high-contrast source for enlarging. (3) In physics: a source of light with extremely small angular subtense e.g. distant star, pin-hole illuminated by large source of light. (4) In optics: theoretical infinitely small source of radiation.

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