Merging Large Lightroom Classic Catalogs

Ten years ago I started in LR and picked up bad catalog management habits which I finally want to get around to resolving.

Current set up is Mac Studio M3 Ultra, 2 tb internal SSD and 256gb RAM. Running Lightroom Classic.

I have two catalogs I switch between-- one with about 90,000 images and the newer catalog with 35,000 images. Virtually all images are Sony .ARW uncompressed or lossless compressed.

The images are spread across 3 external high speed Thunderbolt 4 and Thunderbolt 5 SSD drives-- 1 8tb and 2 4tb. I often have to switch between catalogs depending upon the images I want to work with. Now with LR’s recent switching feature that it as simple as “Open Recent” and letting LR relaunch.

I back up each SSD to a separate external spinning hard drive in OWC drive docks using CarbonCopyCloner and save my catalog backups on another external SSD I use for completed video short projects.

I built smart previews of some imports but not of others.

It seems more convenient to merge catalogs by opening one of the catalogs and importing from another catalog without moving media.

That would give me a combined catalog of around 125,000 and I’m leaving on another photo trip where I anticipate perhaps shooting at least 10,000 images or more.

Is that large a catalog manageable. It sounds like better practice to have everything together since I do like to revisit older edits with the more advanced tools now available.

BUT… is a catalog of 150,000 or so images unweildy and am I better off as is. As it is, I will take a separate drive on upcomg trip and merge those images into the more recent of the 2 catalogs.