Canon A20 - Manual (Page 83)

81
The [Off ] setting helps ensure that file
numbers remain unique over multiple CF
cards. This is useful if you are planning to
download images from the cards to your
computer, since it helps avoid accidental
overwrites that may occur if filenames are
duplicated.
About file numbering...
Image files are assigned numerical filenames
over the range 0001 to 9900. The camera
stores these files into folders, which are
assigned folder numbers from 100 to 998
(except that numbers ending in 99 are not
used). In most cases the camera stores
exactly 100 files into each folder. Because the
camera cannot switch to a new folder when
taking shots in
or mode, however,
some folders may have more than 100
images.
2
Press or button to
select , and then press the
SET button.
3
Press or button to
select [On] or [Off], and press
the SET button.