6
The Press-Focus Lrever, at the top of the shutter, may be used for
' opening the cocked shutter blades for focusing purposes, eliminating
the necessity of resetting it to the Tirne setting for that purpose. Move
the Press-Focus Lever clockwise and down to open the blades; move ii
counter-clockwise and up to close them. This lever will not function
.i: unless the shutter is cocked, and does not interfere in any way with the
., , normal operation of the shutter.
Flash Synchronization
with
Graphex
Shutters
The two contact posts extending from the side of the shutter are con-
nected to an internal switch. in the GRAPHEX (X) Shutters (identified
by a large "X" next to these posts), the contacts are for use only with
high-speed gaseous discharge tubes. When using these be sure to obtain
full wiring or circuit data from the manufacturer of the lamp. Synchroni-
zaiion with standard flash bulbs is effected through the use of a solenoid
or other external synchronized tripper.
. Those GRAPHEX Shutters wiih a dial setting arrangement, shown at
the right in Fig. 2a, have a special gear train providing built-in syn-
chronization. This gear train is automatically engaged as the shutter
iscocked unless the notched synchronization control lever has been moved
to the "OFF" position. Should the shutter aiready be cocked before mov-
ing the control lever from the r\O" or or "OFF" positions to
other positions, the synchronization mechanism will not be cocked unless
the shutter itself is released and recocked; hence, in such an instance
recock the shutter to cause the synchronization mechanism to be en-
gaged. The control lever of the dial setting arrangement on the side o{
the shutter has click stops to permit accurate setting for synchronization.
Make certain that the stop is definitely engaged in its detent before cock-
ing the shutter. The control lever adjusts the delay of the operation o{ the
shutter to correspond with the correct ignition lag of the lamp being used.
Set the lever to the "20" or "M" position on the dial to synchronize the
shutter with standard wire or foiljilled flash lamps such as the G-E and
Westinghouse Nos. 22, Il and 5, and the Wabash Nos. 2, 0, Press 40
and 25 lamps. Set the lever to the "5" or "F" setting to synchronize the
shutter wiih ihe gas-filled SM and SF lamps. When using high-speed
gaseous discharge tubes, set the lever at the "O" or "X" setting, and
follow detailed wirino or circuit hookup data for use with the shutter from
the manufacturer of {he tube.
To use the built-in synchronization, attach the flattened right angle
connection of the A-20 connecting cord to the coniact posts on the
shutter as shown in Fig. 2a, and plug the oiher end into the SERIES
OUTITET at the back of the battery case. In the GRAFLEX Flash Syn-
chronizer Battery Case, this outlet is reached by unscrewing and swing-
ing down the red push button switch. The shutter is released and
synchronization is effected only by the operation of the release lever as
outlined on preceding page.