8. Autofocus measuring flash
• Depending on the camera type, either the AF
illuminator of the camera or that of the flashgun
will be activated whenever the autofocus mea-
suring facility becomes necessary.
• Only the central AF sensor is supported
Low-speed lenses, e.g. with an aperture of
f/5.6 or f/8 (such as zoom lenses), signifi-
cantly restrict the range of the autofocus
measuring flash!
9. Flash techniques and flash functions
Fig. 6: Fill-in flash in daylight (left without, right with fill-in flash)
9.1 Automatic fill-in flash
Some cameras offer the facility of activating auto-
matic fill-in flash control or automatically trigger a
fill-in flash. Fill-in flash will soften harsh shadows
and diminish the contrast, thereby producing a more
balanced exposure when shooting against the light.
The camera's computer-controlled measuring
system automatically selects the shutter speed,
working aperture and light output in such a manner
that both the main subject in the foreground as well
as the background are uniformly exposed.
Please refer to the camera's operating instructions.
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