I have taken over 14,000 photos with my Canon 7D and loaded them into my Windows 7 desktop computer the same way, by inserting the CF card into my computer's reader. The point is that I know how it usually works so this "empty folder" problem is definitely out of the ordinary. To shorten the post I always use the "Safely Remove Hardware and Eject Media" utility before removing the CF. My workflow has been folder based:
- Shoot into a folder.
- Copy the folder to both an internal hard drive for editing etc. and an external hard drive I swap every few days as off-site backup.
- Create a new folder for the next batch of photos, unless the card is about out of space. In that case I format another CF card and remind myself to swap offsite HDs soon. The full card goes in my camera bag, which is my semi-offsite backup against the house burning down.
- When I swap offsite disks I format the CF card in the 7D and move the other CF cards to the "Ok To Use" pocket of my camera bag. If I have time I'll format them as I move them.
I shot tonight's sunset into folder 102EOS7D. Folders 100EOS7D and 101EOS7D had the photos of the two prior shoots since the last offsite backup swap. I put the CF card in the PC and both the last two folders were empty, 101 and 102. I put the CF card back in the 7D and confirmed that both folders 101 and 102 had pictures in them. I attached a USB CF card reader to the PC and inserted the CF card. Folders 101 and 102 were still empty. I put the CF card back in the 7D and the folders were empty! By just trying to read the CF card two shoots of photos went away! Bummer!
I have the photos from folder 101 and tonight's sunset in folder 102 was boring so I decided to troubleshoot rather than try to recover the CF card. I ran Windows Update and nothing was missing. I reformatted the CF card and shot some photos. I found a USB cable that fits the 7D and successfully downloaded the photos in the new folder 100EOS7D.
Any suggestions? The card is fairly new, only in its second or third offsite-backup-swap cycle. It is the largest capacity I've ever had, a Transcend 400x 64 GB CF card.
- I always format in the camera, not Windows.
- Losing photos is serious, how do I help keep it from happening again?
- Is this likely a CF card problem, a Windows problem, a problem with my 7D, or ... ?
- I don't know if this is a possibility, but could there be "bad blocks" in the "FAT" (or whatever, don't know tech details) of the CF card that could produce these symptoms?
- Is there a low-level format utility for CF cards that could identify "bad blocks" and "mark them unusable"? Again, I'm not familiar with CF card details.
- Is there something, given the symptoms, I don't know enough to ask?