particularly advantageous when used with lower shutter speeds (slower than
1/30 sec.) and moving subjects that have their own source of light. With second-
curtain synchronisation, a moving light source will trail a light streak instead of
building one up ahead itself, as it does when the flash is synchronised with the
first shutter curtain. In this way a „more natural" image of the photographic situ-
ation is produced! Depending on its operating mode, the camera sets shutter
speeds slower than its sync speed.
On some cameras the REAR function is not possible in certain operating modes
(e.g., certain vari- or subject programs, or with red eye reduction). In these
cases, the REAR mode cannot be selected and/or is automatically cancelled or
ignored (see camera's operating instructions).
Setting procedure see chapter 9.8.
11.4 Slow synchronisation (SLOW)
A slow exposure (SLOW) gives added prominence to the image background at
lower ambient light levels. This is achieved by adjusting the shutter speed to the
ambient light. Accordingly, shutter speeds that are slower than the flash sync
speed (e.g., shutter speeds up to 30 sec.) are automatically adjusted by the
camera. Slow synchronisation is activated automatically on some camera models
in connection with certain camera programs (e.g., a night shot program, etc.), or
it can be set on the camera (see the camera's operating instructions). No settings
are necessary on the flash unit, nor is there any display for this mode.
Slow synchronisation SLOW is set on the camera (see camera's operating
instructions)! Use a tripod when shooting with slow shutter speeds to avo-
id blurred images!
12 Automatic AF measuring beam
The automatic AF measuring beam is activated in the flash unit by the camera
when the ambient lighting conditions become inadequate for automatic focusing.
It projects onto the subject a striped pattern that the camera can use to focus.
Depending on the camera's activated AF sensor, the AF beam has a range of
approximately 6 m to 9 m (with a standard 1.7/50 mm lens). The maximum
flash range is reached with the camera's central AF sensor. Parallax error bet-
ween lens and AF measuring beam limits the close-up range with the AF measu-
ring beam to approximately 0.7 m to 1 m.
If the automatic AF measuring beam
the „single AF (S)" autofocus mode must be set on the camera and the
flash unit must indicate flash readiness. Some camera models support
only the camera's internal AF measuring beam. In this case, the automatic
AF measuring beam of the flash unit is not activated (as in the case of
compact cameras; see the camera's operating instructions).
Low-speed zoom lenses can significantly curtail the range of the AF measuring
beam!
Some cameras support the AF measuring beam in the flash unit only with the
camera's central AF sensor. If a peripheral AF sensor is selected, then the AF
measuring beam will not be activated in the flash unit!
13 Triggering control (auto-flash)
On some cameras the flash will not be fired when the prevailing light is sufficient
for an exposure. When the camera shutter release is depressed, no flash exposu-
re is triggered.
In various cameras the triggering control only works in the full program mode or
„P" program or must be activated on the camera (see camera operating instruc-
tions).
is to be activated by the camera,
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