The mecablitz receives its information exclusively
from the connected TTL-controlled camera.
Exposure measurement in TTL mode (TTL =
through-the-lens) is completed by the camera's
sensor. This sensor measures the light reaching
the film through the camera lens. An electronic
control circuit within the camera transmits a stop
signal to the flashgun as soon as the film has been
exposed by the correct amount of light; the flash is
then instantly cut out. The advantage of the TTL
mode is that all factors influencing the exposure of
the film (such as filters, change of aperture or
variable aperture zooms) are taken into account.
You need not worry about adjustment of the light
output. The camera's electronic system automati-
cally defines the required amount of light. You can
also utilize various metering facilities (e.g. spot ,
matrix or centre-weighted overall readings) offered
by some cameras.
5. TTL flash control
The Table on page 37 gives the maximum range
for the selected aperture. The minimum lighting
distance is approx. 15% of the maximum thres-
hold range.
If the actual distance is shorter than the
minimum lighting distance, then this may
result in overexposure.
A strip of film must be loaded in the camera if tests
are to be conducted in TTL flash mode.
The effective flash range can only be checked by
the correct-exposure display (o.k.) if the flash is
triggered by the camera and not with the manual
release on the flashgun!
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