A Prontor-Compur connection (also known as a PC connector, PC terminal, or PC socket) is a standard 3.5 mm (1/8") electrical connector (as defined in ISO 519
(1992-11-25). ''Photography -- Hand-held cameras -- Flash-connector dimensions''. Geneva: International Organization for Standardization.) used in photography to

synchronize Synchronization is the coordination of events to operate a system in unison. For example, the conductor of an orchestra keeps the orchestra synchronized or ''in time''. Systems that operate with all parts in synchrony are said to be synchrono ...

the shutter to the flash.

Etymology

"''Prontor''" has its origins in the Italian word "pronto", meaning ''ready'' (and was a leaf shutter made by ). "''Compur''" is derived from the word "compound" (the "'" was a long-lived series of leaf shutters made by ).

History

The term is derived from

brand A brand is a name, term, design, symbol or any other feature that distinguishes one seller's good or service from those of other sellers. Brands are used in business, marketing, and advertising for recognition and, importantly, to create an ...

s of widely marketed photographic leaf shutters manufactured from the early 1950s by two distinct, but now defunct German companies. (which made the '' Prontor-S'' and '' Prontor SV'' models, amongst others) and (the '' Synchro-Compur'' model, successor to the ''Compound'' model). Both companies' brands, ''Prontor'' (from 1953) and ''Compur'' (from 1951), shared a common 1/8"-inch coaxial connector for shutter–flash synchronization. This convergence of design is not as coincidental as it might first appear, owing to the fact that the Zeiss organisation held a significant shareholding in both of these companies prior to the introduction of the shared connector. By the 1950s, Gauthier were manufacturing up to 10,000 ''Prontor'' shutters daily. The Gauthier company's essence lives on as , which is a wholly owned subsidiary of . The Deckel company went bankrupt in 1994.

References

{{ISO standards Electrical connectors Photography equipment