I have come across an excellent free file recovery program that runs in the mac osx terminal.
The program is part of a free suite of utilities called testdisk 6-3 and the interesting bit is called photorec...
It looks complex to a non programmer (like me) as it runs in an old fashioned text box like DOS used to, but in fact it's extremely easy to use...
I have used it when I have accidently FORMATTED!!! an SD card and recovered all the pictures from RAW, (which the program reads as tiffs) which I believe is an awfully difficult thing to do.. and it has saved my life after deleting a card and then aperture lost my latest upload, leaving me with a day's wasted shoot.
Just run the program, follow the simple disk selector, for an SD card choose 'unpartitioned drive' as a final step, and the program will retrieve all hidden data on the card and automatically dump them to a file in your docs folder..
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