How did I lose EXIF data?

After a long shoot of a week I lost most of my EXIF data (exposure values, ISO etc.) from my 20D .CR2 RAW images. Here's what I did, I think: During the week I uploaded the RAW images from the CF cards to a Kanguru traveling hard drive. When I arrived home, I uploaded all the images onto my desktop computer from the Kanguru, and eventually opened with Bridge. Something I did lost the EXIF data. I later recovered it by going back to the Kanguru, uploading again to the desktop computer, opening Bridge, letting it run completely, then looking at the images and EXIF data was there. What mistake did I initially make to have caused this: how can you lose exif data? Obviously I want to know so I can avoid the mistake in the future.

kdoc

I don't think you lost the EXIF data - it's embedded in the RAW files. More than likely, something you did caused a caching problem in Bridge. If this happens again and it doesn't just rebuild (do check for the spinning indicator at the bottom left of the Bridge window), try Tools -> Cache -> Purge Cache for This Folder in Bridge, and see if that helps.


It's also worth upgrading to Adobe Camera Raw 3.3 - there's been a few tweaks here and there, though I can't remember anything specific to do with metadata.

David

Thanks David, I'll try the Purge Cache next time. That's what I thought--that you can't lose that EXIF data...so I was surprised when I did seem to for the first time. That data (Exposure, etc.) isn't in the sidecar, is it? My understanding, as you suggested, is that it's (relatively) forever imbedded in the RAW data.

kdoc

The first time you attempted the upload and viewing the EXIF information in Bridge, you didn't mention how long you waited before attempting to look at it. Bridge takes two passes at each file when you first load the files in; the first a quick pass to provide you with the embedded thumbnail and the second to do a more thorough examination of the data and build its own higher quality preview. I believe the EXIF data appears on the second pass so, if you had a large number of files and didn't wait for both passes to complete, that might have been your issue.

Ahh, that ol' devil "impatience." Once again, that might have been my undoing.

kdoc

As one who has never truly learned the meaning of that word, I feel your pain!!

The EXIF data is in the RAW file - don't forget that the sidecar is generated by the Adobe software, not the camera.

Camera Raw 3.3 seems to explode a lot more information into the sidecar than previous versions, though maybe that's because purged my central cache after reorganising all my photos on my hard disk.


One frustration for me is that Camera Raw 3.3 does extract FEC information, but doesn't make it that obvious. You can see it in the Advanced pane of File Info..., but not anywhere more accessible. That said, Bridge is a very useful application, even if I wish it had more DAM like features.

David