Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 465)

Caution
RAW images or movies cannot be specified for printing. Note that RAW images or
movies will not be specified for printing even if you specify all images with
[
Multiple ].
When using a PictBridge-compatible printer, do not specify more than 400 images
for one print order. If you specify more than this, not all images may be printed.
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