Canon EOS 1 V HS - Manual (Page 58)

Av
Aperture-Priority AE
In this mode, you set the desired aperture and the camera sets the shutter
speed automatically to suit the subject brightness.
The larger the aperture (smaller f-number) the more blurred the
background will become. This effect is suited for portraits. The smaller the
aperture (larger f-number), the clearer the focus will be for both near and
far objects.
* Av is an abbreviation for Aperture value.
With a large aperture With a small aperture
While pressing the
< m o d e >
button, turn the dial until
Av appears on the LCD panel.
Then release the
< m o d e >
button.
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