Canon EOS R5 C VR Creator Kit with RF 5.2mm f/2.8 Dual Fisheye Lens - Manual (Page 459)

Playback Grid
You can display a grid over still photos shown in single-image display on the playback
screen. This function is convenient for checking the image's vertical or horizontal tilt as well
as composition.
1.
Select [ : Playback grid].
2.
Select an option.
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