Canon POWERSHOT SX150 IS User Manual page 98

You can manually set the shutter speed and aperture to shoot images with
the exposure you want.
JV_stands for "Manual".
......Set the mode dial to M.
Aperture Value
Shutter Speed _
Standard
Exposure Level
Exposure Level
Exposure Level _
Indicator
Choose a setting.
Press the [] button to choose the shutter
speed or aperture value.
Turn the !_ii_ dial to set a value.
The set exposure level appears on the
indicator. You can check the difference
against the standard exposure level.
When the difference is more than +2 stops,
the set exposure level appears in orange.
When you press the shutter button
halfway, "-2" or "+2" appears in orange.
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