Canon WFT-R10A Wireless File Transmitter for EOS R5 C & R5 Mirrorless Camera - Manual (Page 84)

3.
Set a caption.
Select [ Caption ] and select the content of the caption on the displayed
screen.
4.
Select [Transfer].
The image is transferred with the caption. When the transfer is
complete, the [
Image transfer ] screen will reappear.
Caution
You cannot manually select images on the [ Transfer with caption ] screen. To
select another image for transfer with a caption, play back that image, then follow
these steps.
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