Nikon D6 Reference Manual page 62

D
Camera Off Display
If the camera is turned off with a battery and
memory card inserted, the memory card icon,
the number of photos in the current folder
( q ), and the number of exposures remaining
( w ) will be displayed in the top control panel.
Depending on the memory card, the camera
may in rare cases not display this information
when a card is inserted. This can be addressed by turning the camera on.
10
Parts of the Camera