Catalogs Main catalog and several others needed to merge

[Edge of Alaska]

Operating System: iMac with El Capitan & MacBook Pro with Yosemite
Exact Lightroom Version: CC 2015.10 (Classic now?)

I started out using Lr with my MBP and external hard drive, which held my photos and backup catalog. I always backup when leaving Lr. Since then, I’ve purchased a new iMac, which kinda complicated my backup, but I made it work as long as I backed up every time I used it with Lr.

Up until this mid summer, I've kept one catalog going for the last 3 1/2 years which I've kept a backup on my MBP and external drive. Whenever I'd use my iMac, I would use the external's latest catalog, and then, when closing, backup onto the external drive and the iMac. Then I would copy that catalog onto my MBP to keep my MBP and external up to date. Then I could take the MBP and external with me when I went to work out of town for 3 weeks at a time. There, I’d find time to occasionally work on photos during those 3 weeks from home.

Now, when home for my 3 weeks, I've on occasion, (and promising to myself that I won’t forget to backup from the iMac to the external and MBP each time), I've done just that and I've quite a few backups now that are on my iMac and not on my MBP and external. I've also later worked on some photos on my MBP and backed them up there and on the external. So, now I have a lot of loose catalogs floating between all three drives. The naming is the default of date + 4 digit number, and most all are zipped files.

Can I somehow merge all of these catalogs since mid summer where each may have adjustments and new shoots that others don't, and combine them into the large catalog? Can I get back to where I was before this happened? Do I stand a chance of losing more recent adjustments with older ones coming in after the merge?

 

[Johan Elzenga]

Yes, it's easy to merge catalogs. Just pick one catalog as the main catalog, choose 'File - Import from Another Catalog', and select another catalog to merge it with the first.

 

[Edge of Alaska]

Thank you, Johan. On some of these catalogs, they will have some of the same files as the main catalog will have. They may have the same adjustments made to them, so overwriting them wouldn't be a bad thing. However, what if I have some adjustments on one of the catalogs that is more current than the other? What will or could happen to the most recent adjustments that I'd want to keep? Will there be a prompt asking me which one I'd like to keep? I may not know the answer to this if I'm not sure which is the most recent. What possible prompts could I encounter during merging, and how should I go about choosing the right functions? Sorry about all the hypothetical questions!

 

[Johan Elzenga]

Thank you, Johan. On some of these catalogs, they will have some of the same files as the main catalog will have. They may have the same adjustments made to them, so overwriting them wouldn't be a bad thing. However, what if I have some adjustments on one of the catalogs that is more current than the other? What will or could happen to the most recent adjustments that I'd want to keep? Will there be a prompt asking me which one I'd like to keep? I may not know the answer to this if I'm not sure which is the most recent. What possible prompts could I encounter during merging, and how should I go about choosing the right functions? Sorry about all the hypothetical questions!

Just give it a try with two copies. You will see that 'Import from Another Catalog' is a fairly intelligent process. Lightroom doesn't 'just merge it', it checks for duplicates and/or two develop versions and gives you options for what to do in that case.