Recovering Footage from a Formatted Card

Sat Aug 19, 2017 5:11 am

Hi,

I had a card accidentally formatted on a shoot yesterday. I called Arri and they told me that footage on formatted cards on Amira's and Alexa Mini's cannot be recovered as it zeros the card. I find it strange that this is the case as accidents do happen, the Arri rep even laughed and said I get these calls all the time. It seems like a poor decision to use this technique to format in an industry that holds safeguarding footage as it's upmost priority. As far as I am aware most other camera systems you can recover data. Is there a technical reason as to why the camera zero's the card?

Thanks Michael
Michael L
 
Posts: 13
Joined: Sat Sep 17, 2016 4:44 am

Re: Recovering Footage from a Formatted Card

Wed Aug 23, 2017 2:11 pm

Hello Michael,

I apologize for our rep’s indelicate reaction. The reason we have to reset the data on CFast cards to zero, rather than just deleting the data mapping tables, is that our cameras can record at a higher data rate than those of other manufacturers. To ensure a good card performance, we have to avoid that the controller on the cards just wanders off to do some flash maintenance while he should be busy storing away footage. This is only possible if the card is fully ‘sanititzed’ or ‘secure erased’ – a method that is also used by the card manufacturers’ own refresh tools, such as https://kb.sandisk.com/app/answers/deta ... fresh-tool

When a card is accidentally formatted, it’s usually an organisational mishap. Someone thought the data was backed up and put it back in the camera to format and re-use. But who is to blame when the pressure is not just on, but constantly increased?
Rather than going paranoid, there are some simple ideas that can help to safeguard the exposed footage.

  1. Always perform a verified (checksum) copy of the data.
    -
  2. Format the card in the computer (any file system, even UDF works).
    Inserting a formatted card into the camera, it will detect that it is not camera-formatted and prompt the user to do that.
    This little change does not cost much time, but eliminates any doubt if the cards are ready to be re-used. Another advantage is, that at this point, the data would still be recoverable. Apple made some changes to their OS, which made Disk Utility pretty useless. I recommend to use a nice little tool called Parashoot https://parashoot.kamerawerk.ch/ which seems to be well accepted among the DITs.
    -
  3. Use colored tape on the card’s crystal case. Red for exposed. Green for “fresh” or re-useable.
    Color-coding allows you to immediately see, which pile of cards to reach for, even if the DIT is not at his station that very moment or you accidentally mixed exposed and fresh cards in your pocket. It’ll also spare you the time it takes to insert a card in the camera and figure out if it was indeed fresh or exposed.
If you work with a new crew, ask them to use this workflow. In the last 100 years, the responsibility of the loader has not really changed. Agreed – the way we (have to) do it, the footage is wiped the moment you confirm ‘erase’ on the camera. But if it’s that or the data is gradually overwritten, or you shoot on film and accidentally use an exposed negative and double-expose, or open a can because you think it was empty, but there is (or now was) some exposed footage inside. It’s all the same.

Best regards
Oliver
Oliver Temmler
Product Specialist Camera Systems/Product Manager Storage Media
ARRI Munich
Oliver Temmler
 
Posts: 37
Joined: Wed Aug 13, 2014 3:16 pm
Location: Munich, Germany

Re: Recovering Footage from a Formatted Card

Sat Sep 02, 2017 5:38 am

Thank you Oliver for the reply.

I thought that might have been the case. I appreciate the advice on how to deal with card management, I have worked in the industry for almost 10 years and this is the first time it has happened. I was just surprised that unlike some other camera companies which have systems that can be recovered, Arri a company that has a reputation for safe guarding its technology had no way of recovering data. It seems a little insane, and yes if the data management system is in place and working there is no need for this. But mistakes happen and it would have been nice to have a fall back. :)

Thanks Michael
Michael L
 
Posts: 13
Joined: Sat Sep 17, 2016 4:44 am

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