Leica R9 Instructions Manual page 175

As the modes P , A , and T already create a nor-
mally exposed photograph using the ambient
light, the flash power should be reduced, i.e. a
flash exposure compensation of e.g. –1 EV to –2 EV
should be set. On modern flash units, the aperture
set on the lens is transmitted to the flash unit
and automatically used as a basis for the
computer's calculation.
Metering takes account of the film speed set on
the camera and any exposure compensation set
for the ambient light and the flash.
Manual flash with fixed output
If the flash unit is used in manual flash mode
with full output or fixed partial output (insofar as
this can be set on the flash unit), there is no con-
trol of the flash light quantity emitted. The expo-
sure modes generally function in the same way
as without flash, but the flash sync speed is used
as the fastest shutter speed. If this limitation to
the flash sync speed results in overexposure, this
is shown in the viewfinder by flashing of the
shutter speed display 2 2 5 5 0 0 (2.9 a) in automatic
exposure modes or, in m, by the light balance (2.9).
The lens aperture to be set is derived from the
flash output, the film speed and the distance to
the subject or, vice versa, the flash partial output
to be set is derived from the aperture, the film
speed, the focal length and the distance to the
subject (see flash unit instructions). However, it
can also be determined by the camera using a
metering flash (see "Flash metering mode before
exposure - F ", p. 178).
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