Using Lightroom on a Mac and PC

[JIMMY1587]

I currently store all of my photo and light room catalog on a portabel ssd drive.    I have been mostly using lightroom between home and work on  windows os.  I recenlty purchased a mac book pro  coding  and some administrative mac support work.    I was able to load my lightroom cataglog on the mac from my ssd drive with no problem.  When I went back to my pc with the portable drive my lightroom catalog told me that I had no photos.  I checked the location of the phots etc and they most of them are point at the ssd drive but with a mac path volume\etc\etc .   Is there away that I can use the catalog on both pc and mac with out this problem.  Thanks 

[AxelMatt]

Make sure that the usb drive is connected to the Windows system every with the same drive letter.

https://www.windowscentral.com/how-assign-permanent-drive-letter-windows-10

[JohanElzenga]

The problem is a bit more complicated than just fixing the Windows drive letter. The problem is that MacOS does not use drive letters, but disk names. The link to an image in a catalog used on a Mac will start with that disk name, and so that image will be 'missing' when you open the catalog on a Windows computer and vice versa. You would have to use 'Find Missing Folder' each time you switch between Windows and Mac. Using a fixed drive letter in Windows will not solve this.

The solution is to make sure that Lightroom uses 'relative links', that do not include the disk. That can be accomplished in the following way: Store your images in a folder (hierarchy) inside your catalog folder. In that case Lightroom uses links like this: .../Folder/Subfolder/Image. The three dots tell it to start with the catalog folder, and so the disk name or drive letter is no longer and issue.

[JIMMY1587]

Is there anyway to reverse this process and get the catalog to work back on the pc ?  Is there a mas way to find all the images again ?  Thanks

[dj_paige]

Find the images (see Figure 4 and associated text):

http://www.computer-darkroom.com/lr2_find_folder/find-folder.htm

[JohanElzenga]

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@JIMMY1587 wrote:

Is there anyway to reverse this process and get the catalog to work back on the pc ?  Is there a mas way to find all the images again ?  Thanks

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Yes, you should reconnect by folders, not individual images. If you reconnect the top folder of a hierarchy, all subfolders and all images inside those subfolders will be reconnected all at once. https://www.lightroomqueen.com/lightroom-photos-missing-fix/

[dsm1212]

Old note but I've been struggling with this and had an epiphany that seems to work well. On macos/linux repeated slashes are actually ignored. So "//foo/Pictures" is the same as "/foo/Pictures" in every way.  So here's what works well for me so far:

1. On windows always use the unc path name for your pics. Not a mount point. In lighthroom these will show like "//MYNAS/Pictures".

2. On macos as root/sudo create the file /etc/synthetic.conf to have a line in it as:

MYNAS   /Volumes

Note that it must be a TAB char between the UNC name of your nas and the string /Volumes. This creates a link so that /MYNAS points to /Volumes. A reboot is required for this to take affect but you can do at end.

3. We want Pictures to be always mounted. You can do this on the mac under preferences User&Groups. Pick Login items, unlock, hit + and add the share like "smb:username@nasip/Pictures". Click "hide" so it doesn't display during login. Then double click to make sure it works. This should remember your password from your keychain.

Reboot so that step 2 takes effect. After you login, use a terminal window to check that your pics are accessible using the same "UNC" path name. "ls //MYNAS/Pictures" shoudl give a list of your shared pictures folder. If so, then you are good to go. Use syncthing to replicate your catalog and you should not have to reconnect anymore as both macos and windows are access the files using the same path.

[dsm1212]

Ah, also, I do all my imports from windows. If you import from mac then you will have to reconnect once when you first hit the new files on windows to get them switched from /MYNAS/Pictures to //MYNAS/Pictures.

[dsm1212]

After a recent update this stopped working. I tried nesting relative to lightroom and had issues converting my library to that. So, I settled on just doing find missing folder after every swap. But, when switching from windows to mac the find missing folder always gives an error, then I exit LR, reopen LR and the folder is working. Maybe this is a rare use case but its not that difficult to test. Or just remember an "alternate path" to try when the first one doesn't work. This would work for other use cases too that involve external drives.