Canon EOS REBEL T6i Instruction Manual page 287

To rotate an image, set [51: Auto rotate] to [OnzD]. If [51: Auto rotate]
is set to [OnD] or [Off], the [b Rotate image] setting will be recorded to
the image, but the camera will not rotate the image for display.
Pressing the <Q> button during the index display will switch to the

single-image display and the Quick Control screen will appear. Pressing
the <Q> button again will return to the index display.
For images taken with another camera, the options you can select may

be restricted.
Q Quick Control for Playback
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