EOS R File Numbering Prefix

6 months 4 weeks ago #653094 by [email protected]
This is my first post and as such I’ll say hi & thank you in advance for any help with the following.

My friend has just purchased a Canon EOS R and from new the file numbering started at 540A0001. My Question is: Why has file numbering started with the prefix 540A?  This appears to me as  being totally random or am I missing something? Furthermore, if this prefix is completely random, what prefix would one usually recommend the file number starts with? 


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6 months 4 weeks ago #653246 by garyrhook
I'll risk sounding snarky.

Has anyone read the manual?

The PDF can be found here:  http://gdlp01.c-wss.com/gds/3/0300032123/05/eosr-ug6-en.pdf

and on page 370 you find instructions for changing the 4 character prefix. The pages immediately prior to that discuss the numbering sequence.

While 540A sounds awfully random, I'll point out the the flange on that body is 54mm across, and this is the first model/body of its type. But it's probably just randomly selected. And you can change it to whatever you wish.

Once my images are in Lightroom, I change the filenames to something based on a brief string, the date, and the original number. Pretty much guarantees unique filenames forever. IOW, those character may not matter depending upon what you do, but I wouldn't rely upon keeping them static. IMNSHO.

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6 months 4 weeks ago #653249 by [email protected]

Thanks for taking the time to respond.

Yes, of course we have read the manual. I wonder if all EOS R's start with this unexplained 540A. When I pick mine up in a couple of weeks I'll find out.

Thanks again.

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