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 pro-
gram, etc.), or it can be set on the camera (see the camera's operating instruc-
tions). 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
avoid blurred images!
11.5 Preflash function for red-eye reduction
Various cameras offer the possibility to activate a preflash for red-eye reduction.
This function only supports the flash unit integrated in the camera. It does not
support external flash units
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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 focu-
sing. 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 ran-
ge of approximately 6 m to 9 m (with a standard 1.7/50 mm lens). The maxi-
mum flash range is reached with the camera's central AF sensor. Parallax error
between lens and AF measuring beam limits the close-up range with the
AF measuring 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 automa-
tic 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!
is to be activated by the camera,