What causes it
Formatting sounds like erasing, and sometimes it is. Often it isn’t.
A quick format writes a new, empty index at the start of the card and leaves everything else alone. The camera now treats the card as blank, but the photos and video are still sitting where they were. This is what most cameras do by default, and what a quick format on a computer does.
A full or low-level format goes further and erases the contents as well. Some cameras offer this as a separate option in the format menu, and a full format on a current version of Windows also overwrites the card.
So the first question is which one happened. If you don’t know, assume it was the quick kind and act accordingly.
What to do right now
- Stop shooting on the card. Not a test shot, not one frame.
- Take it out of the camera.
- Don’t format it again, even if the camera suggests it.
- Write down what did the format (which camera, or which computer) and which option was chosen, if there was a choice.
- Don’t install or run recovery software on the card itself.
What’s realistically recoverable
After a quick format with nothing written since, this is usually a Standard recovery, and most of the contents are still there.
Two things to expect:
- Names and folders may not survive. The format replaced the part of the index that held them. Files found by their contents come back with generic names. Photos usually keep their capture date inside the file.
- Video is less predictable than photos. A long recording can be stored in several pieces, and with the index gone those pieces have to be put back in order. When that’s needed, it’s a Complex recovery.
Older files that were deleted before the format can turn up too. You get a report with file types and date range before you decide anything.
When it isn’t
- It was a full or low-level format. The contents were erased along with the index. There is nothing left to find.
- The card was used after the format. Whatever was written since has replaced what was underneath it. The rest may still be recoverable.
- CFexpress and XQD cards. These behave more like SSDs than like SD cards, and on some camera and card combinations a format may clear the contents for good, even when it looks like a quick one. I can’t tell which until I look at the card. The evaluation is free either way.