Sony HANDYCAM HDR-TG5V User Manual page 81

 SERIES
RESET
Assigns file numbers of photos in sequence.
The file number becomes larger each time you record a photo.

Even if the "Memory Stick PRO Duo" media is replaced with another one,

the file number is assigned in sequence.
Assigns file numbers in sequence, following the largest file number existing
on the current recording medium.
When the "Memory Stick PRO Duo" media is replaced with another one,

the file number is assigned for each "Memory Stick PRO Duo" media.
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