NLP / Lightroom "forgets" that a neg has been converted

I’m currently running NLP v.3.0.2 with LR v13.0.1, but looking at some images I converted over a year ago, the same problem exists, so I don’t think it’s specific to the current version of NLP or LR.

I did some housekeeping - moved converted images from one place to another, not in Lightroom because I use a different DAM. So I then resynced the folders in Lightroom, which in practice means the moved files are re-imported.

After doing this, NLP no longer recognises that the images have been converted. I’ve found that a chunk of metadata shows in LR under “All Plug-in Metadata” for converted images, but that has disappeared from the re-imported files:


I’ve used a file editor to look at an image that shows this metadata in Lightroom, but the metadata isn’t in the file on disk. Explicitly doing a Metadata->Save Metadata to File or Metadata->Update DNG Preview and Metadata makes no difference.

It seems like this metadata is only being held in the LR catalogue, and never written to the file on disk, so all is OK as long as everything remains in the LR ecosystem.

If you moved your files on disk (outside of Lightroom), and then import them from the new location, it will lose its association with your prior Lightroom metadata (including the Negative Lab Pro metadata).

The way to keep everything in sync is this:

  1. In Lightroom Classic, in the “Library” view, find the folder in the left pane where your images used to be found
  2. Right-Click the folder and select “Update Folder Location” - then navigate to wherever you’ve now placed the image

Hope that helps!