apersson850 wrote in post #18490589
You have to take 10000 photos the same day to get duplicates. If you start at 9990, you can take ten pictures before it rolls over, but then it will continue with 0001. It takes another 9989 before you come back to 9990.
As a general advice, forget everything about the file name matching the shutter count. Consider the two as completely separate. That will save you a lot of trouble over the years.
If you really take more than 10000 pictures at the same event, the same day, then import the images with the folder number added to the file name. The camera will increment the folder number each time the image number rolls over. That will give you seven digits, so you can take nine million pictures the same day, before you get duplicate numbers. A camera running continuously at ten frames per second will not make one million images in 24 hours.
It's really quite easy to end up with duplicate file numbers if you use a number of smaller cards say, and when changing cards put a used one back in after a rollover. I usually shoot about 2500 shots at an airshow, using six cards. It can be real easy to put a used card back in the camera, either deliberately to chimp a particular image again, or because you grabbed the wrong one in a hurry. It only takes inserting the card into the camera, with a higher numbered file, to reset the file number count. You can then end up with a lot of duplicate file names. Yes it is mostly unlikely to happen, the numbers don't rollover that often, but it is also really easy to put a card with a very high numbered file in the camera, and bump up that file number count. Personally I don't usually look at the file number suffix when chimping, It's usually is the histogram looking OK as much as anything.
I only know about it, because I did it. Actually not sure if it were to look at an image of the screen, or because I just put a used card back in. It was still some 500 odd images with duplicate file names from a single days shooting.
It would be really useful if instead of the count being reset on insertion, it only happened if you took a shot. Because higher of next number in the camera, or next number on the card is a little less likely to cause errors.