Posted by Les on September 10, 2000 at 20:11:23:
In Reply to: conversion from bulb flash lens to electronic posted by Ken Mitchell on September 10, 2000 at 17:20:48:
: I would like to know if it's possible to
: convert from the bulb flash to the modern
: electronic flash such as a 283 to a crown
: 4x5 with aa Rodenstock, I think there are
: adapters made but I am not sure or if so
: where to get it. Thank you, Ken Mitchell
There are two things to consider when using flash with older
equipment. One is the phyical adapter from an older style sync
socket/terminal. The second is the timing between the flash and the
shutter itself.
Flashbulbs need to be fired slightly ahead of the shutter so they
will be at peak when the shutter opens. This delay is usually 20
milliseconds or 1/50th of a second and is called "M" sync. F sync
is a 5 mil delay. X sync is no delay.
The first problem is the easiest to overcome. A company called
paramount makes custom cords to fit your needs whether you have a
shutter with a bi-post (two small br a s s pins) ASA (an odd
connector with a bayonet connection) or other.
The second is the hardest since an electronic flash doesn't have a
delay, the flash will be over before the shutter opens. (notice
slowing the shutter speed doesn't help since the is tripping the
flash before it opens the lens)
So find out if you have an X sync on the shutter, or if you have
to set a second lever to set a syncronizing timer. Then you should
be okay. If not then you have to get someone to go inside the
shutter and b y p a s s the delay timing circuit