Import not detecting duplicates {same camera, different computer)

[TheBaronVonJ]

I have my photos on a Synology NAS and mounted as a regular network drive on my two Windows computers. The Catalog files are stored in a directory that is synched to the NAS with Synology Drive (like Google Drive or MS OneDrive, but with a NAS instead of public cloud). So I can use the same catalog on either my desktop or laptop. I usually import from the desktop, and it always works to exclude duplicates in the import screen. Today I plugged my camera into the laptop instead, and even though I had the export to only show new photos it showed my everything on the camera, including the 650+ pictures I had already imported. I confirmed in File Explorer the files are there on disk with the same path and filename. 

[moved from bugs to discussion according to the community rules - Mod.]

[Califdan2]

Always a bit risky having the same copy of an LrC catalog accessible from more than one computer at the same time as it's up to you to ASSURE that all the updates from computer A have completed and LrC on computer A is shut down before opening the catalog on Computer B.    

Here are a few things to look at

1)  make sure the laptop is actually pointing to the same catalog as the desktop

2)  Do you do any renaming of files in LrC?

3)  Are both computers running the same version of LrC?

[TheBaronVonJ]

Risk of accidentally using Lightroom from both at same time is known and accepted.

1) Definitely the same catalog file. I check in the Drive client that it pulled the latest version from the NAS before double-clicking the lrcat file to open it. And I have a Collection for photos that need face tagging so I check the numbers on that after opening.

2) No. I primarily use Lightroom for organization by metadata (tagging and albums/collections) so hat I can ignore the file paths and names. I also double-checked that the destination path and filenames shown in the import dialog exist in File Explorer, including capitalization.

3) Yes. Whenever I log into either machine to use Lightroom I let CC run updates before opening the app. They're both on 13.1.

[Califdan2]

I'm stumped.  

I'm wondering if the preferences files might be the culprit.  The preferences file is not stored in the same folder as the catalog and you haven't mentioned that this file is kept in sync between the two machines.  So try this.  With LrC shut down on both machines, copy the preferences file from the first machine to the 2nd and see if the problem changes.

[TheBaronVonJ]

Where is that stored?

[GoldingD]

he Catalog files are stored in a directory that is synched to the NAS with Synology Drive

I could be reading that wrong. So I will ask, where is your catalog? On a local hard drive, or on the NAS?

[TheBaronVonJ]

> where is your catalog? On a local hard drive, or on the NAS?

Yes. 😋 It's on a local disk (internal) but the Drive application syncs the directory with my NAS. 

[GoldingD]

If you were syncing like that but to the Cloud, specifically OneDrive, then that could be an issue when the sync is slow. The slow sync could be causing issues.

So, how quick is your Ethernet connection to that NAS?

[TheBaronVonJ]

Wifi 6 mesh with 2.5 Gbps ethernet backhaul. My desktop and laptop are connected with WiFi, generally at least 400 Mbps. But I'm not switching between them within minutes. Friday I was on the desktop. Then I checked in Drive client that it had finished syncing the catalog files. Then on Saturday I was on the laptop, and I made sure it had synced the files down before opening the catalog. And the duplicate photos in question go back to mid-July. I see the originals there in Lightroom on both computers. It just wants to import them again if I'm on the laptop.

I clicked to unselect all and manually selected the ones I wanted to import, and selected a few too many by mistake (like 3 or 4) and the imported copies all had a " (2)" added to the filenames since the original filenames already existed in the destination. And both the old already-tagged and the newly-imported-with-unique-filename-suffix-added duplicates were shown side-by-side in Lightroom.