Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 477)

2.
Select an item, then select images.
You can select multiple images to process at once.
Selecting images
Turn the < > dial to select images to process, then press < >.
Press the < > button.
Selecting range
Select the first image (start point).
Next, select the last image (end point).
Press the < > button.
To process other images, repeat this step.
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