Posted by Les Newcomer on August 22, 2000 at 16:58:47:
In Reply to: Solenoid?? posted by Ron Crawford on August 22, 2000 at 16:31:51:
Sure,
Back when flash bulbs were first made there was no direct
connection to the shutter. Shutters had no synchronization.
Photogaphers used an "open flash" method-- they opened the shutter,
fired the flash manually (the flash unit usually a modification of
a light socket and flashlight case).
Soon people started experimenting with essentially an eletric
finger to trip the shutter. That is what the solenoid does--it
trips the shutter when the flash bulb is at its brightest.
When properly hooked up on a Speed or Crown, to make the exposure
you press the red button. This brings current to both the solenoid
and the flash unit.That means that the flash is firing the shutter,
not the other way around!
The flash bulb needs a head start-- about 20 miliseconds, before the shutter should open, that's why the solenoid has such sloppy linkage. Also it allows the solenoid some interia to trip the shutter.
Les