Nikon D800E User Manual page 74

Photographs taken while On is selected contain information on
camera orientation, allowing them to be rotated automatically
during playback (_ 266) or when viewed in ViewNX 2 (supplied)
or in Capture NX 2 (available separately; _ 389). The following
orientations are recorded:
Landscape (wide) Camera rotated 90 ° Camera rotated 90 °
orientation clockwise counter-clockwise
Camera orientation is not recorded when Off is selected. Choose
this option when panning or taking photographs with the lens
pointing up or down.
[] Rotate Tall
To automatically rotate "tall" (portrait-orientation) photographs for
display during playback, select On for the Rotate tall option in the
playback menu (_ 266).
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