This is of concern for those who care about privacy minutia. Sometime between darktable 3.0 and darktable 3.2.1 a “Document Name” exif tag started appearing in exported photos. I only noticed this recently looking on Flickr at images I uploaded starting in 2020. It seems this also only shows up in TIFF exports and not JPEG.
Bug or Feature?
Obviously, not a big deal for most people. But for me this raised some privacy/security issues. The folders on my computer might reveal information that I don’t want made public when I upload my photos to the internet.
For example. I might have photos organized like this:
/home/mysecretname/Pictures/Actual-Name-of-Secret-Location/Actual-Legal-Name-of-Model/img1123.cr2
And you can see that this would place information that I did not intend to be public onto the internet wherever I display these photos.
On Flickr you can hide all EXIF data. Exiftool and MAT can scrub exif and metadata before upload But, I like most of the other camera and shooting information to be displayed. (Others are concerned about camera serial numbers and dates in EXIF data also.)
How can the user fix this?
Dt now gives some control over what exif data is exported.
Hidden in the export module is a exif and metadata options interface. You can find this in the Export module hamburger menu > preferences.
To deal with the Document Name tag, click the " + " button, and find the Exif.Image.DocumentName tag. Add this to the list and then change the formula to anything else to ensure that this is written as something other than the full image path.
The screenshot shows I changed Exif.Image.DocumentName to $(FILE_NAME) which will print just the file name and not the full path.
In this interface you can see you can control many other aspects of metadata including being able to turn off printing things like exif or GPS tags entirely. It’s more of a trial and error to modify some tags as it seems some are camera dependent.
more info about metadata preferences in the manual
Finally, if something is really sensitive, just don’t put it in digital form.
“If you want to keep a secret, you must also hide it from yourself.”
― George Orwell, 1984