Data recovery
 

Last weekend I had to shoot a Wedding and I used the 7D to cover the entire bridal preps. I used the sandisc 16GB which had about 600 pics on it which I deleted before using the card. During the bridal preps, at one point I had a message saying something like memory card error but I checked to see if I had my images or video clips and I was able to see them so I kept on recording until the compact flash was full.
Then I downloaded it to my laptop and deleted all the files but did not format it.
I then reused the card.
When I came home I found out that there are no video clips but the old pics that I deleted prior to the bridal preps were still there.
I used about 3 different data recovery software and all I got was those pictures and the last video clips from the ceremony but nothing from the pre ceremony.
any suggestions??

Thank you!

wow.. thats pretty scary to hear about, sorry for you (and sorry i dont know anything about data recovery)

it is very scary knowing this recording sys is not 100%.

Sounds like your data is not recoverable.

Prevention for the future...

1. Do not just delete material from the cards. Once you have it copied to 2 different media (2 external drives, optical media etc.) and the copies are tested, put the card BACK IN THE CAMERA and FORMAT the card (especially just before using it on a wedding)

2. At the first sign of memory card error or problem STOP RIGHT THERE and power down the camera, pull the card and put it in a media case, and put a fresh formatted card in and continue working. Very quickly repose and reshoot what you can of what you've already shot in case what's on the first card is not recoverable.

When you get back home immediately copy the contents of the problematic card to a hard drive and then see what you have.

3. DO NOT FILL THESE CARDS UP! When 20MB and 30MB hard drives were what we had a lot folks pretty much filled them up until we learned that it was in the last 10% of capacity the chances of file allocation table error increased astronomically. I had 2 instances of "scrambled" hard drive, then I began to consider the last 20% "off limits" and after that I never experienced a corrupted drive.

These media cards have a file allocation table and if that gets corrupted you can easily lose the data on the card. I watch usage and when I hit 75% "full" I start looking for a stopping place to switch cards, putting in a freshly formatted media card.

4. Watch battery level. If the battery does not have enough left to complete a "write" to the card you may have a corrupted card as a result. And to me this means DO NOT USE AFTERMARKET BATTERIES in the 7D or 5D MkII, these batteries do not communicate with the camera and can't display battery info. You never know where you really stand.

5. Slow down and give the camera plenty of time to complete writing to the card before opening that door to change cards.

6. NEVER delete files or format in the computer. With most cameras this must be done in the camera the card will be used in.

So far by following these simple rules, I've not had a problem with data loss in the camera.

You can try "Data Recovery 3" for Mac

When in the field it should be SOP to download to two separate drives.

It seems foolish but man it can really save the day.

Paul Hudson
Lizardlandvideo.com
Phoenix Video Production

Google "reverse engineering" in your area. In my former work place, we use a company that helps us recover deleted video files from hard drives and CF , they charge a lot but they get the job done. They call their process reverse engineering.

My 2 cents. Good luck.