🚀 go-pugleaf

>FP stands for bulbs designed for focal plane shutters. They have a long
>burn time, at least as long as the shutter curtain travel time.

   Yeah, by the strangest coincidence Shutterbug has an article on flash
bulbs this month and I just read the same thing.

>M was for medium delay bulbs. There were also short and long delay bulbs,
>but I do not remember (from my reading, I never used any flash bulbs
>except some #25B's with a Brownie Hawkeye) their codes.

   According to the article there were "SM" bulbs with 1/200 flash
durations. They didn't give durations for other types. There are 
probably lots of old photography books running around with that kind
of info if anyone wanted to know it.
   By the way, they mentioned a guy who takes large (12X20 inch negatives)
group portraits. He uses flash bulbs because he gets more light for the
dollar. Equivalent electronic flash would cost him $70,000 in equipment,
result in massive tangles of cabling, would weigh half a ton, and would
consume 15,000 watts of electricity. His flash equipment cost him $500,
weighs 200 lbs, and uses trivial amount of electricity.
-- 

--Brian M. Godfrey
  Sequent Computer Systems Inc.
  !tektronix!sequent!brian