Nikon D300 User Manual page 79

discuss this function more deeply in the chapter titled
Chapter 5. Auto image rotation causes the camera to record
the angle at which you are holding it as part of the image's
metadata. Auto image rotation should be set to On so that an
image will report how it should be displayed on the camera's
Monitor and on your computer later.
In other words, Rotate tall and Auto image rotation work
together to display your image in the correct orientation.
Rotate tall gives you the choice of how the image is viewed
per the orientation information it finds in the image's
metadata. Setup Menu > Auto image rotation causes the
camera to store how the image was taken so that it will know
whether the image is a vertical or horizontal composition. It
can then report this information to the Rotate tall function.
My Recommendation: I leave Rotate tall set to On. That
way I can view a portrait-style image in its natural, vertical
orientation without turning my camera. Be sure you
understand the relationship between this function and Auto
image rotation, which stores orientation data with the picture.
I always set Rotate tall and Setup Menu > Auto image
rotation to On. That lets me view images in the correct
orientation on my camera's Monitor and later on my
computer screen.
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