Canon EOS 60D - Manual (Page 106)

106
The file number is like the frame number on a roll of film. The captured
images are assigned a sequential file number from 0001 to 9999 and
saved in one folder. You can change how the file number is assigned.
The file number will appear on your computer in this format:
IMG_0001.JPG.
1
Select [File numbering].
Under the [5] tab, select [File
numbering], then press <0>.
2
Select the file numbering method.
Select the desired setting, then press
<0>.
Continues the file numbering sequence even after the card is
replaced or a new folder is created.
Even after you replace the card or create a new folder, the file
numbering continues in sequence up to 9999. This is convenient when
you want to save images numbered anywhere between 0001 to 9999 in
multiple cards or folders into one folder in your personal computer.
If the replacement card or existing folder already contains images
recorded previously, the file numbering of the new images might
continue from the file numbering of the existing images in the card or
folder. If you want to use continuous file numbering, you should use a
newly-formatted card each time.
3 File Numbering Methods
Continuous
XXX-0051
Card-1
XXX-0052
Card-2
File numbering after
replacing the card
Next sequential file number
100
XXX-0051
101
XXX-0052
Card-1
File numbering after
creating a folder