Sony ILCA-99M2 - Manual (Page 382)

Format the memory card on this camera. If you format the memory card on the computer, the
memory card may not be usable depending on the format type.
It may take a few minutes to complete formatting, depending on the memory card.
You cannot format the memory card if the remaining battery charge is less than 1%.
[421] List of MENU items Setup
File Number
Selects how to assign file numbers to recorded still images and MP4 movies.
Menu item details
Series:
The product will assign numbers to files sequentially up to "9999" without resetting.
Reset:
The product resets numbers when a file is recorded in a new folder and assigns numbers to
files starting with "0001".
(When the recording folder contains a file, a number one higher than the largest number is
assigned.)
Hint
The setting for [File Number] will be applied to both slot 1 and slot 2.
Even if you change the setting of the recording destination, the file numbers will be sequential across
the two memory cards in each slot by setting [File Number] to [Series].
[422] List of MENU items Setup
Set File Name
You can specify the first three characters of the file name for images you shoot.
MENU
→
(Setup)
→ [File Number] → desired setting.
1
MENU
→
(Setup)
→ [Set File Name].
1