Canon EOS REBEL T6i Instruction Manual page 93

v Brighter
The picture will look brighter.
x Darker
The picture will look darker.
y Monochrome
The picture will be monochrome. You can select the monochrome
color to be blue, black and white, or sepia. When [Monochrome] is
selected, <0> will appear in the viewfinder.
Shoot by Ambience Selection
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