Canon A540 - Manual (Page 48)

46
The aperture adjusts the amount of light entering through the lens.
When you set the aperture value, the camera automatically selects
a shutter speed to match the brightness.
Selecting a lower aperture value (opening the aperture) allows you
to blur the background and create a beautiful portrait. A higher
aperture value (closing it) brings the entire range from foreground to
background into focus. The larger the aperture value, the greater
the range of the image brought into clear focus.
Setting the Aperture
PowerShot A540
! If the shutter speed is shown in red, the image is
underexposed (insufficient light) or overexposed (too much
light). Adjust the aperture value using the
or button
until the shutter speed display turns to white.
! Some aperture values may not be available with certain
zoom positions
(p. 47) .
In this mode, the shutter speed range with synchronized flash
is 1/60 second to 1/500 second. The aperture value setting
may therefore be changed automatically to match the
synchronized flash speed even if its value was set previously.
Aperture Value Display
!
The larger the aperture value, the smaller the lens aperture.
F2.6 F3.2 F3.5 F4.0 F4.5 F5.0 F5.5 F5.6 F6.3 F7.1 F8.0