Canon 188A - Manual (Page 12)

Choosing an Aperture and Reading its
Value
There is a choice of two apertures for auto­
matic flash photography To select an aper­
ture, set the Aperture/MANU selection
switch to the upper or middle position; the
aperture value will appear
in
the Aperture/
MANU window The aperture will change
depending on the setting of the ISO film
speed When ISO 100 film is used, for ins­
tance, the upper position is f/2 8 and the
middle position is f/5 6
When the Aperture/MANU selection switch
is set on the lowest position, "MANU" ap­
pears in the window As this indicates
manual flash photography, automatic flash
photography is impossible.
• In automatic flash photography, if the
ISO film speed is set between gradua­
tions, such as 64 or 80, the aperture
value indicated is between click-stops
on the aperture ring. In the case of the
F-1 (depending on its exposure mode),
AL-1 or AV-1, set the lens' aperture
ring to the click-stop of the larger aper­
ture