Canon EOS R50 Mirrorless Camera (White) - Manual (Page 189)

Still Image Aspect Ratio
You can change the image's aspect ratio.
1.
Select [ : Still img aspect ratio].
2.
Set the aspect ratio.
Select an aspect ratio.
To proceed without changing shooting area display, press the < >
button.
JPEG images
The images will be recorded with the set aspect ratio.
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