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?