Best software to recover video files on reformatted SD and CF Cards? Or worth seeking professional help?

Question

Hi all,
The person I work for has mistakenly re-formatted a collection of SD and CF cards (incl. Sony F3, AJA Ki Pro Mini). He needs to recover video files.
Is it worth it to have the cards professionally recovered at a place like Tekserve, or is there a software program anybody here has had success with? There seems to be a lot of recovery software out there and it's hard to tell what's trustworthy. I should mention that the software doesn't have to be free, it just has to be effective and cheaper than a professional recovery.
A few other stray but important questions:
-What are the risks of running a recovery program that fails? In other words is it possible for software to damage the old data so that no other program has a chance of successfully recovering it?
-Most importantly: is it possible to recover at least some data from a card that has been reformatted and then recorded over a bit, but not all the way? I have read that if the whole card has been recorded over, the old data is irretrievable. But there's only a little bit of new material on this card. 
Thanks!

Answer 1

Reformating storage devices usually involves deleting the catalog that tells the OS where files start and end. The files are still there unless you have chosen a secure erase where the systems writes zeros over the whole drive several times (sometimes known as a DoD format).
What this means is as long as you do not try to write to the media, the files are still there. Best practice would be to clone the media then work on the clone. This way you do not introduce any addiional changes.
The more important element of your question is "can I get these files that still exist off the the media?". The answer is a resounding "maybe".
I have used FileSalvage to try to recover material from a failing hard drive. It was pretty successful with small files (Word docs, Acrobat files, Adobe Illustrator images and the like)  but considerably less successful with large video files. I believe it is because video is more sensitive to end of file (eof) markers and if those are not found, the whole file is useless.
If you have reused the card, the chances of getting anything go WAY down as the way files are written to storage devices is not that orderly. Bits get written all over the drive/ flash storage. When there is no catalog to tell the OS what memory locations have a purpose, new files can be written over multiple old files. Will this completely remove any chance to recover your material? Most likely, but if you are purchasing software anyway it will not cost you any additional cost to try on those cards. You might get lucky.
Also, in the locking the barn after the paddle is lost upstream, this is why I always create two copies of the contents of cards before I start editing. 1 copy goes on the on-line editing RAID and the other copy go to an archive drive. Then once a week, I'll back up the archive drives in the studio to a set off-site. This way I have 3 copies while I'm working and 2 copies once the project is closed out. Given the low price of hard drives, it's easy to create redundant backups.
Good luck,
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