Tusk is a Mac app that automatically backs up your project folders to multiple locations and tracks where every file lives — even when your drives aren't connected.
Your Lightroom catalog is a single file that holds every edit, rating, flag, and collection you've built across every shoot you've ever imported. Lose it and your RAW files are still on disk, but they're unedited originals with no organization. Years of culling and grading, gone.
Lightroom's built-in catalog backup runs on a schedule and writes a second copy to your Mac. That protects against catalog corruption, which does happen. It does not protect against a drive failure, a stolen laptop, or accidentally deleting the wrong folder. Both copies live on the same machine.
TL;DR: Back up your Lightroom catalog (.lrcat file) and its preview/cache folders to at least two separate destinations: an external drive and ideally cloud or a NAS. Keep Lightroom's built-in backup on for corruption protection, but treat it as one layer in a proper 3-2-1 setup, not the whole system.
What Files Does Lightroom Actually Need Backed Up?
Lightroom Classic stores your work in a few distinct places. Each one matters.
The catalog file (.lrcat) is the brain. It contains every edit, metadata change, collection, and keyword you've applied. This file changes every time you sit down to edit.
The catalog previews folder (usually YourCatalog Previews.lrdata) holds the JPEG previews Lightroom generates so you can browse and edit without loading full RAW files every time. You can regenerate previews from the RAW files if you lose them, but rebuilding a large library takes hours.
The smart previews folder (YourCatalog Smart Previews.lrdata) matters if you use smart previews for offline editing. Same regeneration story as regular previews.
Your RAW or DNG files live wherever you told Lightroom to store them during import. The catalog points to these files by path. If you move RAW files without updating the catalog, Lightroom shows missing files. Back up the RAW folder and the catalog together, or back up the catalog to a location that mirrors the same folder structure.
For Capture One users, the equivalent is the session or catalog folder (.cocatalog or session files) plus the image folders it references. The same principles apply.
Where Does Lightroom Store the Catalog by Default?
On Mac, Lightroom Classic defaults to ~/Pictures/Lightroom/. Your catalog file sits there alongside the preview folders.
You can check the exact path in Lightroom: Lightroom Classic > Settings > Catalog Settings > General. The "Location" field shows where your active catalog lives.
If you've moved your catalog to an external drive (common when internal storage is tight), note that path. Your backup strategy needs to follow the catalog wherever it lives.
How Lightroom's Built-In Catalog Backup Works
Lightroom can back up the catalog automatically when you close the app. You configure this under Catalog Settings > Backup.
Options include backing up on exit, weekly, or when Lightroom detects the catalog hasn't been backed up in a set number of days. Lightroom writes a .zip file containing the catalog to a folder you choose.
What this does well: protects against catalog corruption. If the main .lrcat file gets damaged, you unzip the most recent backup and you're back.
What it doesn't do: copy anything off your Mac. The backup zip lands on the same machine (or a folder on the same machine). A drive failure takes both the catalog and every backup zip with it.
Keep the built-in backup enabled. Set it to run on exit or at least weekly. Point the backup folder to a location that your broader backup system also covers (see below). But don't stop there.
The Proper Lightroom Catalog Backup Workflow on Mac
The goal is three copies across two media types with one offsite, applied to both your catalog and your RAW imports. The 3-2-1 backup framework covers the general structure. For Lightroom specifically:
Copy 1: Working catalog on your Mac (or fast external SSD). This is where you edit.
Copy 2: External drive backup. A labeled SSD or HDD that gets a verified copy of the catalog folder and your RAW imports folder. Update this continuously or every editing session, not once a month.
Copy 3: Offsite. Cloud storage (Backblaze B2, iDrive, Backblaze Personal) or a drive stored at another physical location.
Step 1: Keep the catalog and RAW files in predictable folders
Put your catalog in a known location. Put RAW imports in a dedicated folder structure (e.g., RAW/2026/ClientName-ShootDate/). Avoid scattering files across the Desktop or Downloads. Backup tools work better when paths stay stable.
Step 2: Back up the entire catalog folder, not just the .lrcat file
Copy the catalog file plus its .lrdata preview folders together. If you only copy the .lrcat file, you lose previews and smart previews. Lightroom can rebuild them, but that's downtime you don't need.
The folder to back up looks like:
MyCatalog.lrcatMyCatalog Previews.lrdata/MyCatalog Smart Previews.lrdata/
Step 3: Use automatic backup, not manual dragging
Manual copying works until you forget. For an active catalog that changes every editing session, you want a tool that watches the catalog folder and pushes changes to your backup destinations as they happen.
Scheduled backup (nightly ChronoSync or Carbon Copy Cloner tasks) is better than nothing, but you'll be hours out of sync during a long editing day. Continuous watching is better for catalogs that change frequently.
Step 4: Verify transfers
A corrupted catalog backup is worse than no backup, because you think you're covered. Use a backup tool that verifies each transfer with a checksum (BLAKE3 or MD5). If the copy doesn't match the source, you want to know immediately.
Step 5: Test a restore once
Pick a random week-old catalog backup and open it in Lightroom (File > Open Catalog). Confirm your edits and collections are there. A backup you've never tested is a hope, not a plan.
Lightroom Catalog Backup With a NAS
If you run a Synology or QNAP NAS on your network, the catalog can live on the NAS or sync to it as a backup destination. Lightroom performance over a network is slower than a local SSD, so most photographers keep the working catalog on a fast local drive and sync to the NAS as a backup layer.
Set the NAS up as one destination in a wider workflow alongside your RAW imports. Key point: RAID on a NAS is not a backup. It protects against drive failure inside the NAS, not accidental deletion or ransomware.
How Tusk Fits the Lightroom Workflow
I built Tusk for project-based backup on Mac. For Lightroom, you create a project pointed at your catalog folder and your RAW imports folder (or a parent folder that contains both). Add your backup destinations: external drives, S3-compatible cloud, Google Drive.
Tusk watches both folders continuously. Every time Lightroom saves the catalog, the updated .lrcat file gets pushed to your backup destinations with BLAKE3 verification. Same for new RAW imports after a shoot.
The part that matters for photographers with multiple drives: Tusk tracks where every file lives, including drives that are unplugged. Six months later, when a client asks for reshoots from a 2024 wedding, you can see which drive holds that catalog and those RAW files without plugging in every drive you own.
Before you delete local copies to free up Mac storage, Tusk runs a preflight check: it verifies each file is physically present on every connected backup destination. Files that aren't confirmed stay put.
Tusk doesn't replace Lightroom's built-in catalog backup (keep that on for corruption protection). It replaces the manual "drag the catalog to an external drive when I remember" step.
FAQ
Every editing session, ideally in real time. Your catalog changes every time you flag a keeper, adjust an exposure, or add a collection. Lightroom's built-in backup on exit is a good minimum (weekly at worst). For continuous protection, use a backup tool that watches the catalog folder and syncs changes as they happen. Nightly scheduled backups leave you exposed during long editing days: a full day of ratings and edits won't be backed up until midnight.
No. Lightroom's built-in backup only copies the catalog file (as a .zip). It does not touch your RAW or DNG imports, your preview folders on disk, or your exported JPEGs. You need a separate backup strategy for your RAW imports folder. The catalog and RAW files should be backed up together, or at least on the same schedule, so paths stay consistent and you can recover both from the same point in time.
On a fast local drive (internal SSD or portable NVMe SSD) for editing performance. The default location is ~/Pictures/Lightroom/. If internal storage is tight, you can move the catalog to an external SSD, but avoid spinning HDDs for the working catalog because Lightroom feels sluggish over slow drives. Regardless of where the working catalog lives, back it up to at least one other drive and one offsite location. Never let the external drive be your only copy.
Yes, if your catalog lives on your Mac's internal drive. Time Machine will include it in hourly snapshots. The limitation: Time Machine doesn't back up external drives by default, so if your catalog or RAW files live on an external drive, Time Machine won't cover them. Time Machine also gives you no per-file status. You can't ask 'is my catalog fully backed up right now?' before deleting local copies. Time Machine is worth keeping on as one layer, but photographers with external drives need more.
Open your most recent Lightroom catalog backup (.zip) from the folder configured in Catalog Settings > Backup. Unzip it, then in Lightroom go to File > Open Catalog and select the unzipped .lrcat file. If the built-in backup is recent, you lose at most a few days of edits. If you have no backup, third-party catalog repair tools exist but success isn't guaranteed. This is why the built-in backup on exit is worth keeping enabled even when you have a broader backup system running.