Possible Cause of Corrupted NEFs

[cliffcheney]

A colleague had his D700 files corrupted. We think it happened on a Windows PC long after they were originally copied from the cards.

What can cause this? Why are the files still close to the correct size?

We are hoping to prevent this going forward.

[Phil Harvey]

The most likely cause is a memory card problem.  Usually in this case the images are gone for good.  I have often seen files that are the correct size, but filled completely with binary zeros, or sometimes seemingly random data.  If ExifTool can still recognize the file, then there is a chance it may be repaired.  Otherwise, there is a remote possibility that a JPEG preview may be extracted.  If you send me a sample (philharvey66 at gmail.com), I'll take a look.

- Phil