Canon EOS REBEL T8i Advanced User's Manual page 307

[ ] Monochrome Adjustment
[ ] Filter effect
With a filter effect applied to a monochrome image, you can make white clouds or green
trees stand out more.
Filter
N:None Normal black-and-white image with no filter effects.
Ye:Yellow The blue sky will look more natural, and the white clouds will look crisper.
Or:Orange The blue sky will look slightly darker. The sunset will look more brilliant.
R:Red The blue sky will look quite dark. Fall leaves will look crisper and brighter.
G:Green Skin tones and lips will appear muted. Green tree leaves will look crisper and brighter.
Note
Increasing the [Contrast] will make the filter effect more pronounced.
Sample Effects
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