XMP files not being generated

[johnp17654037]

Hello friends

MacOS and latest LRC

I have just noticed that files imported on and after July 1, 2024, are not creating xmp files, even after editing. The raw file is there, and when opened in LRC, the edits are there, but there are no xmp's.

Any idea why?

John

[Jao vdL]

Just making sure you know:

1. xmp files are only created when you set the preference to write a copy of all changes into xmp files. This is done in catalog settings->metadata. These files are only backups. The actual settings are written inside the catalog. 

2. Lightroom Classic does not "open" files. You have to import them into the catalog. It is possible that you are not looking at the raw files that are actually in the catalog but are looking at the location from which you imported into another destination. If you did point 1, make sure you are looking at the actual raw files by right (or control) clicking on the image in the Classic catalog and selecting "show in finder/explorer"

3. If 1 and 2 are checked, realize that for dng files (and tiff, jpeg, etc.) the xmp is written inside the file's metadata. For those files you will not see a separate xmp even if you are writing those. 

[johnp17654037]

Thank you for your help! I just clicked the setting to write to xmp, and they have now been created, but...

1. xmp files are only created when you set the preference to write a copy of all changes into xmp files. This is done in catalog settings->metadata. These files are only backups. The actual settings are written inside the catalog. 

NOPE! didnt know that!!!!! If there is no xmp, and I lose the cat file, I assume I lose all my edits?

If there are no xmp's, would Bridge or other browsers show only unedited versions of the photos?

2. Lightroom Classic does not "open" files. You have to import them into the catalog. It is possible that you are not looking at the raw files that are actually in the catalog but are looking at the location from which you imported into another destination. If you did point 1, make sure you are looking at the actual raw files by right (or control) clicking on the image in the Classic catalog and selecting "show in finder/explorer".

I must have used the wrong terminology. I was looking at the raw file from within LRC.

3. If 1 and 2 are checked, realize that for dng files (and tiff, jpeg, etc.) the xmp is written inside the file's metadata. For those files you will not see a separate xmp even if you are writing those. 

I didn't know about the tiff and jpgs not using xmps.

[JohanElzenga]

> If there is no xmp, and I lose the cat file, I assume I lose all my edits?

Yes, that is why making a catalog backup each time Lightroom quits is essential. Not everything in the catalog is stored in XMP, so XMP side files are an addition to your workflow if you want to, but cannot be seen as a full backup in case the catalog file is lost.

[Jao vdL · Accepted solution]

Yeah very important to realize that Lightroom classic works very differently from Bridge. It uses a centralized database (the catalog) to store all edits. As Johan says, it is important that you use the backup function often for that reason. It is really rare that a catalog file becomes corrupt but not unheard off. Writing the xmp sidecars is a convenience feature that does come at a performance cost. Small but sometimes noticeable. Also important to know that as Johan says, not all info can be stored in the sidecars such as what collections things belong to and that makes protecting your catalog file important. Lastly, if you happen to edit the sidecars externally to Classic such as by using camera raw on the files from Bridge, those changes to the xmp are NOT carried back into Classic. In fact if you have automatic writing of sidecars turned on, they will just get overwritten. You can read the data from the sidecars manually into classic but as said, that is not automatic!

If having the sidecars as main repository of edits is important to you, you are better off using Bridge. You can now also use the local browser mode (I wish Adobe added this to Classic) in the cloud version of Lightroom and that also uses the xmp sidecars as main repository, but this local browser mode is far less powerful and full featured than bridge or classic. 

[johnp17654037]

Thank you, Jao. Both your and Johan's replies have been very informative..