Undelete RAW files on SD card

[SimonW]

In a senior moment I deleted files from my camera's SD card by accident.

(What I actually did was drag them to a window on my PC hard disk as I've done thousands of times before, only it wasn't the window I wanted - the recycle bin window as open as well and I put them there instead, then emptied the trash)!  I realised right away, removed the SD card and protected it, so the files are still there somewhere. I've used "Recuva" occasionally in the past, but probably not for my own camera files, which are Adobe DNG format made by the Pentax camera. Recuva quickly found the correct number of files and showed the .DNG file type. However, I cannot open them. Lightroom, Photoshop Elements and Corel Paint Shop Pro all refuse to recognise the file type.

It's no big deal luckily as I can probably repeat the shots next time the weather and lighting are right, but it's annoying, and I'd like to know if there's a fix in case such a thing ever happens again. I found several Apps on line which claim they can but their reviews are awful, specifically they don't play well with RAW files, and they're too expensive for the trivial files I've lost.

The question really is, can anyone recommend a free or cheap file recovery application which is guaranteed to open Pentax DNG RAW files?

Cheers, Simon

[Hinfrance]

Sorry Simon, can't recommend a free recovery programme. Luckily for me, some time ago a friend needed a couple of SD cards recovered from a 'holiday of a lifetime' jaunt to South America and paid for a copy of Ease US data recovery for me. Worked a treat. Might be a useful thing to keep in the armoury for more important file losses. I also came to have a license for File Scavenger which is also very good - I think someone else paid for that

[Oldboy]

This is strange, as all a file recovery program does is rebuild the Fat file, allowing your software to see the files on the disk. It doesn't alter the photo file itself. If you have file protection on the SD card on, then it can't rebuild the Fat file. Without the Fat file no program can open the files. So you need to turn off the file protection and rerun the program which should recreate the Fat file. This may take a long time depending on the number of files. 

[SimonW]

Hi Oldboy,

I do agree that's what I thought. But Recuva doesn't do that. It "recovers" any deleted files it finds to a different folder - on a different disk, of your choice. Recuva is probably intended for accidentally deleted files (where the FAT file is of course intact) rather than for corrupted disks.

A slightly late thought - perhaps Recuva does in fact create a new FAT - a temporary one on the same disk it recovers the files to rather than the original location.

Cheers, Simon

[Oldboy]

Hi Oldboy,

I do agree that's what I thought. But Recuva doesn't do that. It "recovers" any deleted files it finds to a different folder - on a different disk, of your choice. Recuva is probably intended for accidentally deleted files (where the FAT file is of course intact) rather than for corrupted disks.


Cheers, Simon

When you delete a file, all you are doing is removing the entry for that file from the Fat file, the original file is unchanged. Any recovery program works by recreating the Fat file. The Fat or File Allocation Table tells the operation system where all the bytes of your image/file are on the disk. The more you use a disk the more fragmented it becomes so, a image may be spread over different parts of the disk. Years ago when you brought a memory card it use to include a image recovery program on the card. I know Scandisk use to do this but they don't do it now. Microsoft used to bundle an undelete program with Dos 6 but they don't now. There are many free recovery programs on the internet which should rebuild the Fat file regardless of the file format type. 

[SimonW]

Hi Oldboy,

I know what you've said is correct, and widely described. But is there a slight catch? I have read several reviews of recovery software which say they can be good with jpgs but very hit and miss with RAW from various cameras. Perhaps it's easy to put complete file back together, but without the FAT not quite so simple to correctly identify the file type. And I know that the version of DNG created by Pentax cameras is not the same  as one created via Pentax RAW and the Adobe file converter.

It's all of some academic interest of course, but in practice it would be useful to be able to confirm that recovery software will do the intended job before purchasing it, and the paid for ones I've looked at do not allow this. A trial might (like Recuva) show that they are recoverable but require payment for doing so - after which (perhaps like Recuva) it might not work anyway.

By the way, Recuva is from Piriform, the same manufacturer as CCleaner.

Cheers, Simon

[Mick]

Found this, but not sure if it's any good. It claims to recover a lot of different formats including PEF and DNG and it's a free version. https://www.stellarinfo.com/free-data-recovery.php

Disclaimer:  Try at own risk. 

[SimonW]

Hi Mick,

Thank you for trying to help.

This appears to be good software, allowing choice of locations etc for input and output. The free version will recover up to 1GB of data before you need to pay. It appeared to recover the 26 deleted DNG files totalling about 650MB. And unlike Recuva my Photoshop Elements opened the files in its RAW editor as it should. However, every file looks exactly the same - a white background with several thin red diagonal lines.

I'm confident my card hasn't been written to since I deleted those files, so they are still intact on it somewhere. My conclusion is that Stellar is probably well worth trying for other file types, but not Pentax DNG.  (I'm writing this in case any friends here are interested).

Anyway, it's not really a problem for me, I can take the shots again and probably better....

Cheers, Simon

[Hinfrance]

I know you don't want to pay for a recovery programme, but I just deliberately deleted all of the memory card in my K20D and ran File Scavenger - it recovered the lot (all pefs) in moments. The files are all complete including metadata. But I accept it is rather expensive

Or you could try Ease US: https://www.easeus.com/datarecoverywizard/free-data-recovery-software.htm

I've got a glitch with my licence for the pro version at the moment - windows upgrade issue probably, just checking with the vendors.

[Paul Montgomery]

It's not a recommendation as I've never used it, but I've heard good things about zero assumption recovery:
https://www.z-a-recovery.com

Good luck
Paul

[Oldboy]

It's not a recommendation as I've never used it, but I've heard good things about zero assumption recovery:
https://www.z-a-recovery.com

Good luck
Paul

I've used that and it works a treat. When I used it was for Dos that wasn't NT. It might have a NT version now. 

[SimonW]

I tried File Scavenger since Howard reported it worked with Pentax PEF (Raw files) and again found it couldn't recover my Pentax DNG files. I've given up now, it just isn't worth spending more time on. But thanks again to everyone for their suggestions.

Simon

[StephenBatey]

What I actually did was drag them to a window on my PC hard disk as I've done thousands of times before, only it wasn't the window I wanted - the recycle bin window as open as well and I put them there instead, then emptied the trash

I can't help with the recovery, but a thought did just occur to me. If you normally drag the files across, do you (after emptying the card) then format the card? If you don't, you are making file recovery much more difficult if you ever need to.

[SimonW]

Good tip Stephen, and yes, if I empty the card I do format it (in the camera). I then immediately take one jpg photo and protect it from deletion. That one is a photo of my contact details in case the card or camera gets mislaid. (Not that I'm careless, it just seems like good practice).

[Oldboy]

Good tip Stephen, and yes, if I empty the card I do format it (in the camera). I then immediately take one jpg photo and protect it from deletion. That one is a photo of my contact details in case the card or camera gets mislaid. (Not that I'm careless, it just seems like good practice).

Formatting the card in camera just removes the fat file not the pictures/photos. The only way to remove them completely is to do a low level format via the computer and this will take as long as writing the original files to the card.