Canon AE-1 - Manual (Page 67)

Shutter Speed and AE Coupling Range
The shutter speed and AE coupling range
are indicated in the table. If any combination
outside the coupling range is made, the
coupling range warning lamp will blink, as it
does when warning of underexposure. Since
the lamp serves a dual function, check that
the shutter speed is within the coupling range
before assuming that the light level is too low.
Overexposure Warning Mark
When the lighting of the subject is too
bright, the meter needle will rise into the red
zones of the aperture scale. The red area is
divided into two parts. The top part is a
warning for use with a lens having a minimum
aperture of f/22, while the bottom part is for
use with a f/16 minimum aperture lens.
When the meter needle enters the red
area, incease the shutter speed and correct the
exposure.
With the FD 100mm f/4 S.C. Macro lens,
which offers a minimum aperture of f/32
available, if you want to photograph at its
minimum aperture of f/32 and the meter
needle points to the red area, do the follow­