Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 614)

4.
Rate the image.
Press the < > button so that the current rating is outlined in blue, as
shown.
Turn the < > dial to select a rating mark, then press the < >
button.
When you append a rating mark to the image, the number beside the
set rating will increase by one.
To rate another image, repeat steps 3 and 4.
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