Canon PowerShot G6 User Manual page 92

Manually Setting the Shutter Speed and Aperture (continued)
See page 206 for settings that can be changed in this mode.
For the correlation between aperture value and shutter speed,
see page 83, 84.
If you wish to change the exposure, adjust the shutter speed or
the aperture using the main dial.
The brightness of the LCD monitor matches the selected shutter
speed and aperture value. If the flash is set to (Flash on,
with red-eye reduction) or (Flash on), or you have attached an
external flash, the LCD Monitor will always appear bright.
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