Recovering deleted images from SR card??

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First of all you will need a card reader and not go through the camera to read the card. Also since you wrote more files after deleting them the first time, it is possible that the first round could be completely gone or corrupted.

Try this, works for me!
http://www.cgsecurity.​org/wiki/PhotoRec

If your pc is running windows, do a "search" and limit the date range as needed. Further limit the search to only jpg or cr2 extensions. If they are on the pc windows will find them.