Re: Zeiss Ikonta Shutter - Rapid and Synchro - both have flash?

"Ken Hart" <kwhart1@[EMAIL PROTECTED]
>

> but I think a solenoid would require high current (amperes)

It's not really current but 'ampere-turns' that are required.
If you wrap twice as much wire around the coil you need 1/2 the
current.

However, when you lower the current requirement you also increase
the inductance of the solenoid, and this makes it slow.

To make the solenoid faster you can increase the voltage and
decrease the wire size to limit the current.

The whole thing becomes a 5-way trade-off and you can make
a solenoid that works on any voltage and current you wish if
you are willing to trade off speed, strength and/or stroke
(and cost).

> while a flash bulb would require votage.

It's both voltage and current: volts * amps = power,
and it is power that lights off the flash.  The
bulb can be designed for any voltage desired.
Most flash bulbs will fire at 3 volts.  The
22.5 V BC (battery & capacitor) flashes were more
reliable as they had enough voltage to punch-through
any dirt in the bulb contacts or poor contact between
the spun wires in the bulb.

Because the 22.5 batteries can't deliver much current,
the battery charged a capacitor - the capacitor can
deliver high current but only for a very short while,
which is OK as it only takes a few milliseconds to get a
flashbulb ignited.

-- 
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.darkroomautomation.com/index.htm
n o lindan at ix dot netcom dot com