1DMK3 multiple card writing question

I just bought a used MK3 and set the recording up to separate cards .. RAW to the main CF, and JPEG L to the backup SD card.

So what I do is download the files from the CF card to my computer, then put the CF card back into the camera, erase all files & format the card. But when I shoot again all the old backup files on the SD card are transferred to the CF card.

For example if I do a shoot of 1,000 files then download those files from the CF, erase the files from the CF, format the CF, then do a second shoot of 50 files when I download the second shoot there are suddenly 1,050 files on the CF card .. not good. So somehow existing files are being transferred from the SD to the CF. I can stop this by formatting the SD after every CF card change but I don't want to do that because I sometimes still need to have the backup files on SD.

I have my MK2N set up for recording exactly the same way and it just records new shots on the CF as they are taken, and does not transfer old files from the SD card every time I put a new CF card in.

I must be doing something wrong with the folders or setup but I don't know what .. help!

I never used the simultaneous write on the MkIII as I'm using the SD card as an overflow of my primary card. However here are the few thoughts that come in mind:

What kind of naming of files are you doing? reset for each new card? continuous?
Do you keep the camera on when you remove the CF or SD? Then it may revert to another scheme as both card are not present.

photopat wrote in post #14041485
I never used the simultaneous write on the MkIII as I'm using the SD card as an overflow of my primary card. However here are the few thoughts that come in mind:

What kind of naming of files are you doing? reset for each new card? continuous?
Do you keep the camera on when you remove the CF or SD? Then it may revert to another scheme as both card are not present.

Thanks .. I'm using continuous file naming and have tried both power on & off .. same result. The only thing that I can see the cam reverting to after taking the CF out is it then uses the SD card as the display instead of the CF.

I must be missing something ..

What happens if you don't remove the files from the card while it's away from the camera, but uses the camera's "Delete all pictures on card" command instead? Same thing?

apersson850 wrote in post #14041611
What happens if you don't remove the files from the card while it's away from the camera, but uses the camera's "Delete all pictures on card" command instead? Same thing?

Thanks .. I never delete with the computer, always in camera. And I've tried erasing all on card, erasing all in folder, and also formatting the CF card after erasing. Same result.

The only way I can find to stop the transfer from SD to CF is to format both cards after the CF download, which is no good for me as I still want the backup files to stay on the SD card.

I've read & re-read the manual on this and still can't seem to find the problem, and it does not do this with my 1DMK2N when set up the same way. Could be a SD card problem, I'm going to try a new one later today.

mmahoney wrote in post #14041307
So what I do is download the files from the CF card to my computer

How do you do this?

I use Lightroom 3.6, and it's excellent at identifying duplicate photos. It doesn't depend on the file name alone; it looks at the EXIF data.

I don't, however, have a dual-card camera, so I can't say how Lightroom would handle that situation.

But I have a 5D Mark III with dual slots on order, and I'm curious. I shoot RAW+JPEG for some reason, and I'm interested in having the camera write RAW files to the CF card and JPEG files to the SD card.

I'm curious as to how Lightroom will handle that. When I insert the CF card, it will obviously detect all the new photos and import them. But when I insert the SD card, will it know to pair up the JPEG files with their RAW counterparts?

InterMurph wrote in post #14041913
How do you do this?

I use Lightroom 3.6, and it's excellent at identifying duplicate photos. It doesn't depend on the file name alone; it looks at the EXIF data.

I don't, however, have a dual-card camera, so I can't say how Lightroom would handle that situation.

But I have a 5D Mark III with dual slots on order, and I'm curious. I shoot RAW+JPEG for some reason, and I'm interested in having the camera write RAW files to the CF card and JPEG files to the SD card.

I'm curious as to how Lightroom will handle that. When I insert the CF card, it will obviously detect all the new photos and import them. But when I insert the SD card, will it know to pair up the JPEG files with their RAW counterparts?

Lightroom will import the file and adds a "-2" on the end end of the duplicated file number, and "-3" for a third duplicate and so on. But you can set up LR to not import suspected duplicates but I feel that poses a small risk of it not importing a file that it sees as a dupe but is actually not.

In your case it seems you're wanting to actually have both RAW and JPEG where in my case I'm just looking for insurance that if my CF card with RAW fails I have some kind of backup with my JPEG's on the SD card.

Anyways my problem seems related to the SD card .. my computer failed to recognize it so I tried a different card in the camera and now all is well.

I'm pretty sure in your case LR will import both sets of files and simply tag a number at the end of the file.