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Flash techniques
Tecniche flash
Técnicas de destello
8.2 Flash exposure correction
The automatic flash exposure system of the mecablitz is
based on a 25 % reflectivity of the subject (average reflection
factor for subjects shot with flash). A dark background that
absorbs a great deal of light or, alternatively a light back-
ground that reflects a great deal of light (e.g. backlit scenes),
would invariably result in over- and underexposure of the
subject.
Exposure correction in auto flash mode
To compensate the above effect the exposure can be cor-
rected by opening or stopping down the camera’s aperture.
With a predominantly light background the sensor of the
flash unit will interrupt the flash prematurely with the result
that the subject is underexposed. Alternatively, with a dark
background the flash will be cut off too late. The subject will
be overexposed.