Canon AE-1 - Manual (Page 46)

Concernir >9 the Exposure (Shutter
Speed and Aperture Coupling)
In order to obtatn the correct exposure, it
ti necessary to correctly metch the shutter
speed with the aperture. The shutter speed
and the aperture are the main factors in
controlling the arrKKint of light which is
flowed to strike the film, and when they
change, the quality of the image upon the film
also changes.
1 Effects of Chenging the Shutter Speed
The explanations below are portirtent to
photography with fast moving subiects or
vvhen it is intended to convey the feeling of
movement in a photograph.
If. as in exampto A. the s^oto token at
a shutter speed of 1/2&0 sec., the movement
will be frozen.
If. as in example 6. with the same
sgb^ The photo is taken at a speed of 1/60
sK. though the sub)eci is somewhat blurred,
movement is well expressed, it is only a
matter of aesthetics as to which of these
(holographs is the best.
Depending on the selection of the shutter
speed, you can freely control the expression
of movement.