Nikon D780 Reference Manual page 81

•
If two memory cards are inserted, the camera will show the
number of additional photographs that can be recorded to
the card in Slot 1. When the card in Slot 1 is full, the display will
show the number of exposures remaining on the card in Slot
2.
•
Values over 1000 are rounded down to the nearest hundred.
For example, values between 1400 and 1499 are shown as
1.4 k.
•
If the memory card is full or locked or a card error has
occurred, the icon for the affected slot will flash.
First Steps
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