EOS R8 lost videos on SD card - how to recover?

[hellsq]

I lost some videos after dummy battery cable was disconnected. I can see 0 bytes mp4 files and I can see that my SD card have lots of used space - exactly like it have some videos on it.

Usually EOS utility helps, but this time I didnt notice this and moved all 0 bytes files from SD to my PC, so, there is nothing to recover in EOS utility.

I run chkdsk utility with /f argument and it creates FOUND.000 directory with .CHK files, looks exactly same size and amount as lost videos - but I cant open it in any software.

So, even if I did something wrong already - is there a way to restore video files that was lost after camera was powered off during recording?

[Waddizzle]

I have serious doubts that you can recover anything after running CHKDSK with the fix switch enabled. 

I think it’s time to replace and retire that memory card.  Buy a new full sized card and use the camera to low level format it prior to first use.  

It should go without saying that you should never share your camera’s memory card with another device. You should not use the memory cards to store files, either. 

[hellsq]

But chkdsk gives me bunch of restored .chk files. This method works fine with another cameras and audio recorders, but in case of R8, .chk recovery tools that I use, didnt identify them as .mp4 files.

Why this card needs replacement? Anyway, I shoot only for personal puposes, this isnt my job or something highly important. Problems only appears after R8 poweroff during recording, tools like disk drill also dint find any bad sectors on this SD card.

[Waddizzle]

I wouldn’t trust the card.  Do you?  

I assume you are using a full sized card and don’t share it with other devices.  What brand and size is the card?  

[hellsq]

I trust it just because it works perfectly all the time if I use camera correctly and dont allow poweroffs by accidental disconnecting dummy battery. And even in this situation I get .chk files. Or you trying to tell me that Canon R8 must leave correct .MP4 files even after camera poweroff during recording?

Kingston Canvas Go Plus 512GB full-size SD, I use it only in R8 (and it was initially formatted in R8) and in my PC's cardreader. What difference does it make? Card by itself looks totally fine and working.

[Waddizzle]

It sounds like your video files were not properly closed when the dummy battery was disconnected. That could explain why CHKDSK is coming back empty. 

[hellsq]

Why empty? Sorry, my english is bad, but first things that I wrote in this topic was about incorrectly closed recordings and chkdsk results is here, bunch of .chk files in found.000 folder - I just dont know how to open or use this recovered, but incolmpleted files.

[Waddizzle]

I have used a program called ISOBuster to read file fragments.  But I was using for MUCH smaller files that contained text.  

[hellsq]

I use deCHK, it works perfectly with absolutely same problem with USB recordings from Behringer XR16 mixer, but it cannot recognise .CHK files from Canon R8. And I am talking about large .chk files with 4k video.

[Waddizzle]

It’s not going to find files that were never properly closed.  If they were never closed, then they never really existed.