T3D Re: Flashflood? (TECH-3D digest 362)

[bobh@xxxxxxxxxxxxxxxxxx]

RE: Bob Maxey wonders if anyone using "slow peak, medium 
peak, or flashflood flashbulbs??"  This is sort of convoluted 
terminology. Chemical flashbulbs were class F, M or FP, meaning 
5ms, 20ms or 31ms (ms = millisecond) to peak brightness from 
ignition. The Class F were for box cameras and just a glob of 
primer that burned quickly and could use the X setting if no F 
setting. The normal bulb was Class M with a 20ms time to peak 
and needed to be fired before the shutter opened. i.e. X setting for 
strobe or electronic flash would miss them. The FP bulb had two 
cuts of foil so a double peak and was designed to burn long enough 
to allow a focal plane shutter slit to cross the film plane. In banonet 
size in was a #6 in screw base a #31. I have no idea what Bob 
means by a flashflood bulb?  BobH  (Ex Westinghouse Lamp 
engineer in Photolamps.)
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