Canon EOS-1D Mark IV - Manual (Page 89)

File Numbering Methods
Auto Reset
The file numbering restarts from 0001 each time the card is
replaced or a new folder is created.
Even after you replace the card, create a folder, or switch the target
card (such as □ ^ D), the file numbering continues in sequence from
0001 for the images saved. This is convenient if you want to organize
images according to cards or folders,
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 save images with the file numbering starting from
0001, use a newly formatted card each time.
File numbering after
replacing the card
File numbering after
creating a foider
File numbering is reset
Manual Reset
To reset the file numbering to 0001 or to start from file number
0001 In a new folder.
When you reset the file numbering manually, a new folder is created
automatically and the file numbering of images saved to that folder
starts from 0001.
This is convenient if you want to use different folders for the images
taken yesterday and the ones taken today, for example. After the
manual reset, the file numbering returns to continuous or auto reset.
О if the file number in folder No. 999 reaches 9999, shooting wili not be
possible even if the card still has storage capacity. The LCD monitor wiil
dispiay a message to replace the card. Replace it with a new card.
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