Recovering Images

[klindup]

I guess it had to happen one day.  I thought I had downloaded all my images from my 60D and carried out a low level format of the card.  it was then I discovered that I had failed to download one group of images.  Have I lost them forever or are there tools out there that can recover the lost images?  I did remove the card from the camera as soon as I discovered what I had done so nothing has been written to the card since formatting.

Thanks
Ken Lindup

[KeithB]

Low level format implies that it would require the NSA* to get them back, but:
http://www.computerworld.com/s/article/9224577/6_data_recovery_tools_for_SD_cards_USB_drives_and_more

I still have trouble believing that you need multiple writes of ones and zeros to prevent someone from getting the information off a hard drive, but...

[Bob Atkins]

I wouldn't bet that a so called "low level format" of the card is a true low level format. It might be, but it might not be. I'd still try one of the many image recovery utilities on it. I can't particularly recommend any one of them, but see http://www.online-tech-tips.com/free-software-downloads/free-photo-recovery-software/ for some suggestions.

If one doesn't find anything, try a different one!

It depends on what did the "low level" formatting. I think some of the Canon Powershots really did do low level formatting which would make the data non-recoverable. If you did it on a PC I think Vista and Windows 7 (and 8?) do destroy the data, but I don't think XP actually does. I'm not sure what the typical EOS DSLR format does, but I think it just deletes the file information block, not the data.

Basically, it never hurts to at least try to recover the data. The recovery programs won't make anything any worse. They only read data from the card.

If I want to erase the image data from a card so it can never be recovered, I use a dedicated file wiping utility.

Good luck!

[klindup]

Thanks for the advice gentlemen.  I formatted the card on the 60D rather than merely deleting the images.  I read somewhere that formatting was better than deleting and that is what I have always done. 

Ken

[KeithB]

The thinking is that the disk controller in the camera might not be very good, and *might* hose the directory with a lot of adding/deleting, so it is better to just wipe the whole thing. I don't know that this has ever been proved, but we are talking about our precious images here...

[Bob Atkins]

I don't think there is any harm in reformatting the card rather than deleting the images. As far as I know the 60D doesn't actually do a low level format of the card, so you can recover the images. I'm not 100% sure what the difference is (if any) between "Delete all" and "Reformat" when it comes to Canon EOS DSLRs down at the bit level on the card. Formatting clearly doesn't do a low level format of the card which (a) would take longer and (b) would delete all the actual data by writing zeros over it and so making recovery impossible. I assume that "delete all" deletes all image file references in the fAT (file allocation table) which were in the DCIM folder. "Format" may wipe the FAT removing all references to all files in all directories including any temporary files and anything in any other folders as well as the DCIM folder. In each case it's equivalent to tearing the index out of a book. The data is still there but the OS has no index to it and so assumes it's not there and writes over it.

Note that "delete all" deletes all the image files that are not marked by the user as "protected", while format deletes all the files, even those marked as "protected" by the user. That's probably the main practical difference between the two as far as a user is concerned.