RAW - how to ensure no data loss/proper recording at full card?

[charlesbrepsant]

Hi there everyone,

Thank you to everyone responsible for bringing us ML, such an amazing hack. 

I am using 5d3 with ML nightly build 1.1.3 to record RAW footage continuous 1920x1080 with Sandisk 160mb/s cards and Lexar 1066x (mostly 128Gb cards).  Everything works great, except the following issue that I find quite hard to handle: 

I often end up filling up a full compact flash card by recording RAW in MLV format, and the recording stops with the error message "Card really exFat?".  The final shot is corrupted and unusable when back in post.


As you can imagine this can really be tough in some cases.... Can anyone advise on any ways to tackle this problem?

My workflow at the moment is as follows: in order to prevent corrupt frames as I need as much CPU available for the recording as possible, so I record in Hack No Prev mode, with all global draw/overlays disabled.   In general I leave on the "Status When Recording" to "Icon" which has been a success until now in that I did not get any corrupted frames.  I need to try the "Debug" mode to see if it gives me corrupted frames or not, as that mode gives the amount of space that the current recording is taking.   By being aware of how much is left on the card before starting recording, this could be a workaround, but definitely not ideal.

Also, one other thing that bugs me is that after finishing an MLV recording, the amount of space left on compact flash card does not update automatically.  I need to restart camera in order to make it update the correct number.

Would be great to have the community's input on this... I hope solutions are possible. 

Many thanks again.

[Frank7D]

I don't have an ideal solution, but if you time your shots and track the total you will know how much space you have left.
Here's a tool you can use to figure out the capacity of your card given what kind of footage you're shooting.

Also, if you restart the camera and go into the menu and choose "format" (but cancel instead of actually formatting, of course), you can see how much space has been used already.

[charlesbrepsant]

Hey, thanks for your answer, as well as the link to the calculator.  Cool tool.

I knew the trick for looking up the space/remaining time on cards, but again, tough when shooting.  If anyone knows a more pragmatic way....

Maybe something can be done in post to "fix" the last shot that was corrupted?  Since all images are recorded without compression this should be possible, no?

Or just a magical way of displaying the data remaining on card whilst recording... Or any other method really.

Cheers!

[dmilligan]

Most converters should already be able to handle abruptly ending MLV files (RAW format is a different story and another good reason to use MLV instead of RAW).

What converter are you using?

[charlesbrepsant]

Hey, thanks for your response.

I use RAWMagic to convert to compressed CinemaDNG.  Is is supposed to read abruptly ended MLV files correctly?  I can't remember that happening for some reason.

Otherwise which software can you recommend that does that for sure?  Is that how you personally overcome this abrupt ending limitation?

[dmilligan]

RAWMagic is not supported here. This is why.

You can try any of the converters from the sticky threads here: http://www.magiclantern.fm/forum/index.php?board=54.0

If you try MLVFS and it does not handle the shortened files correctly, please send me an example file (preferably relatively small) that doesn't work.

[charlesbrepsant]

Hey, thank you very much for your answer. 

I was not aware of these ethical issues.  I will try MLVFS and/or other converters and let you know. 

I will also in the future refrain from buying any software not respectful of ML's GPL. 

Many, many thanks again.