Sony BRAVIA XR A90K 42" HDR 4K UHD OLED TV - Manual (Page 221)

Help Guide
Digital Still Camera
DSC-RX0M2
Set File Name
You can specify the first three characters of the file name for images you shoot.
Note
Only capital letters, numbers, and underscores can be entered. However, an underscore cannot be used as the first character.
The three characters of the file name you specify using [Set File Name] will only be applied to images you shoot after changing
the setting.
4-748-164-11(1) Copyright 2019 Sony Corporation
MENU → (Setup) → [Set File Name]. 1
Select the entry field for the file name to display a keyboard on the screen, and then enter three characters
of your choice. 2
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