Losing my ratings when changing EXIF time and then refreshing EXIF data in darktable

Hi everyone,

My camera unfortunately doesn’t switch to summer time and back automatically, so I usually have several pictures with the time offset by one hour twice a year.

I prefer to rectify this in the RAW files’ EXIF data by using exiftool.

This time I already imported, rated and edited the pictures in darktable before noticing the offset. Changing the EXIF time outside darktable and then refreshing the EXIF data inside darktable unfortunately removes the rating. I guess that’s because the original RAW does not have a rating, which overwrites the rating in darktable’s database.

Is there a way to only reload the RAW’s EXIF date data?

I know about the geolocation workaround in darktable, but I do not want to use it because I want it to be fixed in the original RAW files without being dependent on darktable.

Thanks!

There is a lua script currently waiting to be merged into the lua scripts repository that will modify the EXIF image time in the darktable database without modifying the raw file. You simply select the file(s), set the adjustment, then apply it all from within darktable.

I will try and get it merged this weekend, so that it is available.

Bill

So you mean the correct way is to adjust the EXIF data in the RAW file and in darktable separately?
Because I do want to modify the RAW file.

Most people don’t want to modify the raws. If you want to modify the raws, then the script doesn’t help you. Modify the raws before you import them, so that you don’t have to reimport them and change your ratings.

Sorry if this is offtopic, but why would people not want to modify the RAWs if the original timestamp is off by one hour?

It’s not off-topic (after all, you were the OP so it’s your topic! :wink: ).

People avoid modifying their RAWs in general, not just to avoid modifying a timestamp. They want to avoid any chance of corrupting the RAWs due to a mistake.

Having said that, these are your RAWs, so nobody can tell you what to do (or not do) to them.

I would have the same problem. I think fixing a technical mistake in a raw file is something different from editing image content.
Wouldn’t it be a solution to do both? Fix the raw file with exiftool and independently fix the database entries with the upcoming script? I’m looking forward to it!

Well, luckily exiftool operates non-destructive in standard settings, so that doesn’t seem like a problem. But I understand the qualms.

Ah, I found an easy solution: use exiftool on both the RAW and XMP files and then rescanning the folder in darktable seems to do the trick.