70D changed sequence numbers from 6.. to 5...

[bob70D]

Month old 70D was issuing sequnce numbers OK in August 31  in the 600 range but on September 2  (the next time I used the camera) the sequence numbers changed to 5000. I manually changed the date to October but the sequence numbers remained in the 5000 range so it probably had nothing to do with the month change. I did a menu RESET,  took a photo and it was just the next number (5102) so no help there. In both cases there is a number 100 and a dash preceding the sequence number. Any suggestions? Thanks 

BTW the camera FILE NUMBERING setting is CONTINUOUS

[Tim · Accepted solution]

Hello bob70D,

The most likely culprit with something like this is going to be the card.  It is very likely that the camera is reading an old file numbering scheme (could even be from another Canon EOS DSLR) and "picking up" where the numbers leave off. 

To test this, and really to resolve this issue, you'd need to format the card.  Only do this in the camera and only once you've backed up your pictures.  First, set the camera's file numbering to Manual Reset and then Format.  It will bring everything back to 0001.  Then go back into the Menu and back to file numbering and choose Continuous this time. 

[bob70D]

I had 2 brand new 16 gig San Disk Extreme HDSC cards that had not been in any other camera. Do not think the problem was caused by another numbering system as the jumped to scheme started at 5000 which would appear to be a predetermined number - not random.

I did as you suggested - reset and format, Both cards were formated. The images on the cards then showed up as 0001 and 0002. I am going to leave the problem open for about a month or so to see if the problem recurs. 

Thanks for looking at my problem.