Nikon Z 9 Reference Manual page 31

•
To format the card using the existing format method, select [Yes
(quick format)].
•
You will also be presented with full and quick format options after
pressing the O ( Q ) and S ( Q ) buttons for two seconds.
D
Cautions: Full Format
•
A full format takes longer than a quick format.
•
Do not turn the camera off or remove the CFexpress memory card until the
message [Formatting memory card.] clears from the display.
A
"Quick Format" Versus "Full Format"
A quick format overwrites only the file system information, leaving the actual
file data intact. In contrast, performing a full format on a CFexpress memory
card deletes all data. We recommend fully-formatting CFexpress memory
cards prior to transfer of ownership or disposal.
New "Full Format" Option for CFexpress Memory Cards
31