Hasselblad 500C/M Instruction Manual page 29

ALTERNATIVE RELEASE METHODS
The camera can be triggered in different
ways, e.g. with a release cord, intervalometer,
by radio control, etc.
The general rule for all release methods is that
the button which triggers the release impulse
to the camera must be kept depressed until
the between-the-lens shutter has opened and
closed completely. This is especially impor-
tant at shutter speeds from 1 to 1/15 s. If the
shutter speed is set at 1 s, for example, and
pressure on the release button is relaxed be-
fore the between-the-lens shutter has had time
to close, the auxiliary shutter will terminate
the exposure prematurely.
Release sockets (Fig. 53)
The front of the camera features two identical
sockets (13) for attachment of a release cord
or a release button. The release button or
shutter release (14) is normally in the lower
socket but can be removed by simply pulling
it out.
FK type cords are suitable release cords.
Release cords
^ tripod should be used when operating the
camera at slow shutter speeds. Camera release
by release cord is then suitable. Release cords
in lengths from 1 ft to 20 ft are connected to
the front sockets (13). Release cords from 100
ft to 600 ft and cords for connection of a re-
charge unit are connected to the side socket
(17). When cords longer than 100 ft are used,
an amplifier should be put between camera
socket and cord.
General
The 500EL/M can also be released by closing
the electric circuit between pins 1 and 3 (see
the circuit diagram in p. 28). External resis-
tance should not exceed 6 ohms if triggering is
to be reliable.
RECHARGING
Recharge unit I is standard equipment with
each new camera and is used for recharging
the camera's batteries.
Move the lever (16) to the L or O position.
Connect the recharge unit to the side socket
(17). Make sure the unit is set at the correct
voltage (110 or 220 VAC) and connect it to a
wall outlet.
Recharging time is about 14 hours for a fully
discharged battery and 28 hours if two bat-
teries are recharged simultaneously. Batteries
should not be overcharged.
Change or recharge a battery as soon as the
camera recycling time becomes noticeably
prolonged. If a battery becomes so exhausted
that the camera stops working or stops in the
middle of a cycle, move the lever (16) to L and
connect the recharge unit.
NOTE! The L setting must be used if the
camera has not recycled fully. 1f the
camera has recycled, either the L or
the O setting can be used for battery
recharging.
Battery charger option
Recharge unit III with a built-in timer is avail-
able as an optional extra.
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