Delete Pictures from Both Slots

G button U D playback menu

Choose whether deleting a copy of a picture recorded to both memory cards with an option other than [Overflow] selected for [Secondary slot function] in the photo shooting menu also deletes the remaining copy.

Option	Description
[Yes (confirmation required)]	Before deleting one copy, you will be prompted to choose whether to delete the other. To choose the option highlighted by default, press 2.
[Yes]	[Same pictures on x & z] is always selected; selecting [Yes] in the confirmation dialog deletes both copies.
[No]	The confirmation dialog displayed is the same as that for pictures for which no second copy exists. Deleting the current picture does not delete the copy.