Nikon D6 Reference Manual page 463

1 Displayed in red if the picture was taken in mode P, S, or A with auto
ISO sensitivity control enabled.
2 Displayed if Custom Setting b7 [Fine-tune optimal exposure] has
been set to a value other than zero for any metering method.
3 Also includes the magnification for pictures taken with a
teleconverter.
4 Displayed only if the picture was shot with a VR lens.
5 Also includes the color temperature for pictures taken using [Auto] or
[Natural light auto].
Photo Information
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