Canon Speedlite 155A And 199A - Canon AT-1 Instructions Manual

Canon Speedlite 155A and 199A
When the Speedlite 155A or 199A is used
with the AT-1, i t is not necessary to set the
shutter speed on the camera a s i s the case with
ordinary electronic flash units. A t any shutter
speed except "B",
the shutter speed is
automatically adjusted to the X synchro-
nization speed of 1/60 sec. a t the time the
flash is charged. To perform automatic flash
photography, set the prescribed flstops on the
lens manually.
The Speedlite 199A is a powerful flash
unit with a guide number of 30 (meters, with
ASA 100 film). To control depth of field, you
can choose between three auto working
apertures which are automatically controlled
to provide a right exposure to the main
subject. The 199A also has bounce flash
capability and, when used with the wide angle
adapter, covers a 24mm lens field.
Both of flashes employ a unique light
sensing system, so excessive reflection from
the central area i s reduced giving better overall
exposure.