Canon EOS R3 Advanced User's Manual page 625

Sending a specified range of images
1.
Press <
2.
Select [Send range].
3.
Specify the range of images.
>.
Select the first image (start point).
Select the last image (end point).
To cancel the selection, repeat this step.
To change the number of images in index display, press the <
button, then turn the < > dial.
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