Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 577)

Index Display (Multiple-Image Display)
1.
Switch to the index display.
During image playback, turn the < > dial counterclockwise.
The 4-image index display will appear. The selected image is
highlighted with an orange frame.
Turning the < > dial further counterclockwise will switch the display
from 9 to 36 to 100 images. Turning the dial clockwise cycles through
100, 36, 9, 4, and single-image display.
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