If you want to try data recovery apps for free then you have plenty of options available for Mac. Go for Stellar file repair http://www.stellarinfo.com/mac-osx-recovery.php, try disk drill for Mac http://www.cleverfiles.com and Softtote Mac recovery http://www.softtote.com . Trying more than 1 tool will help you evaluate & compare the recovery performances. Go for the one which gives back maximum recovery figures.
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