Canon Speedlite 155A - Canon AE-1 Instructions Manual

Canon Speedlite 155A
The versatile circuitry of the Canon AE-1
allows
it
to perform fully automatic flash
photography with the Speedlite 155A es-
pecially designed for this camera. I t is not
necessary to set the shutter speed or the
aperture on the camera as, up to now, flash
photography required.
When the 155A is attached to the AE-1.
set the aperture ring of the lens to the " A
mark and the shutter speed dial to any
position other than "B" (Bulb). With the pilot
lamp of the 155A lighting up, the 155A func-
tions to automatically adjust the camera's
shutter speed to the X synchronization speed
as well as the aperture to the prescribed
fhtop value.
After it flashes, the camera automatically
switches over to the AE photography mode
until the pilot lamp lights up again during
which period
AE
photography can
be
con-
tinued. A steady support may be required if
shutter speeds are slower than 1/30 of a
second.
Like ordinary flash units, you can also
perform flash photography by operating the
aperture ring manually. When you are using a
Canon F L lens which does not allow full
aperture metering, automatic flash photo-
graphy can be performed by setting the
prescribed flstop on the lens manually. In
both cases, the shutter speed is automatically
adjusted to the X synchronization speed of
1/60 sec.
This flash employs a unique light sensing
system, so excessive reflection from the
central area i s reduced giving better overall
exposure.
Moreover, when the main witch of the
Speedlite 155A is turned off, the flash cir-
cuitry is completely cut off and the AE-1
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