Battery–capacitor flash

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Polaroid BC flash model 281

A battery–capacitor flash (BC flash) is a flash photography system used with flashbulbs. Instead of relying directly on the current pulse ability of a battery to directly fire a flashbulb, a battery was used to charge a capacitor that would then discharge through the flashbulb. BC flash units used either 15V or 22½V batteries.


The advantage was that even with an aging battery, the flashbulb would still get a high current pulse and thus reliably fire, although the recycle time between flashes would increase as the battery aged.

See also[edit]


  • Electronics for Photographers, by Marshall Lincoln, Copyright 1966 by Chilton Books, pp 43–54.
  • Capacitors & Batteries, Boston University Physics Department