I'm also wondering how I can prevent this from happening again. I was shooting 4K 10-bit 23.976fps using a Lexar U3 150 mb/s SD card with 128GB of storage (I had used 122gb by the end of the take, and had a few gigs to spare.) I was also using a 3rd party battery by Newmowa, but it had plenty of charge remaining.

Thanks for reading! Any leads at all would be hugely appreciated.

I spent about 4 hours this morning doing some foley and voice over work on location, I tested the audio after each take and it all played back just fine and sounded great (trusty H4n). When I got back to the editing suite and popped the card in, it took about 30 seconds for the card to pop up, which was my first red flag. Then I opened it up and it looked empty at first, then I literally watched the H4n file structure slowly appear before my eyes one folder at a time, second red flag. I attempted to copy the data over to my worktable drive and it started the visual indicators of a transfer process but never began the actual transfer. A left the work station alone for about 45 minutes and came back to a spinning wheel of death and discovered that finder had crashed without transferring a single bit or byte of the data. I tried to relaunch the crashed finder but it didn't reopen, I was left staring at my desktop backgrounds and nothing more and had to manually reboot the machine. This is where it got really fun. Now the machine would not boot up with the SD card inserted, it would just hang on the boot screen. I tried a few times, then powered down and removed the SD card and the machine started up fine. Then I put the SD card back in and the drive pops up, but as soon as I go to open it, finder crashes again. I can't even get far enough to see inside the folder anymore. Ok, so it's clearly a corrupt SD card and I'm ready to introduce it to it's new home: the garbage can, but first I need to attempt to retrieve any data I can to save me from asking my client to take another 4 hours to re-record all the audio (which, as you all probably know, is never as good the second time around). Not the end of the world if it comes to that, but I'd really rather not have to go that route, if it is at all possible to avoid. I tried the same card in a different card reader on a different work station and got basically the same results - unable to access the drive or data. So I started some research into data recovery software options and decided to give Stellar Pheonix Mac Data Recovery a try. Even the software couldn't see the drive in it's more common data backup and retrieval services, but I discovered could see a 'Generic 16GB SD' drive under the 'Image Creation' option, which it states is for exceptionally problematic corruptions. Basically it aims to create a mountable .DMG image containing every sector on the drive (including ones not in use). So I went for it. The software begins the sector processing on block 0, where it sits for about an hour. I was just about to give up and shut it down when all of a sudden it progresses, identifying block 0 as being fine, but block 1 as a bad block and continuing on, the next 30 blocks (700000 sectors) go by like a breeze, all fine, but then it gets stuck again around block 30. I'm going to leave it over night and sleep with my fingers crossed, but if anyone else has any insight or experience with a similar issue, please share your experience. I will update this thread tomorrow with results of the attempted data recovery, good or bad.

I've shooted recently a 5 minutes Video using "12/15 GOP 'DREWnet' " on my gh2. As soon as I try to copy the file from the SD to my HDD, it freezes at a certain point. I am able to playback the video on the sd card, and I discovered that at the middle of the Video VLC freezes and crashes, therefore one frame must be damaged. I've tried several things (I am on Windows 7):

run chsdsk /r on the sd card (its freezes too), mpeg sptreamclip (can not open it), convert the footage in premiere and After effects, but while converting the programs crash (no respond), I tried to run testdisk (but as I did not delete the file, it didnt recover it), transcoding with 5DtoRGB freezes at the exact spot where VLC crashed, Converting with Adobe media converter also failed, Virtual Dub doesnt open it.

Is there any chance to copy the files at least as chunks? The file is 3,6 GB big