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.
The fastest safe way to back up a terabyte-scale footage library on a Mac is local-first: two external drives holding full verified copies, with cloud reserved for a small, irreplaceable subset like selects and project files. Copying 1TB to an external SSD takes around half an hour. Uploading the same terabyte on a typical home connection takes days, and most working libraries aren't 1TB. They're 5, 10, or 20.
Cloud backup isn't wrong. It's wrong as the primary home for bulk footage, and the math below shows why.
TL;DR: Uploading 1TB takes about 2 days at 50 Mbps and over a week for 5TB. Local drives move the same data in minutes to hours. So: two external drives with full verified copies for the bulk, cloud for the small subset you couldn't reshoot. Tusk runs exactly this setup, syncing to all destinations in the background and verifying every file with a checksum.
How long does it take to upload 1TB?
Upload time is bandwidth math, and the numbers are worse than most people expect. Assuming your connection sustains its full rated upload speed the entire time:
| Library size | 25 Mbps up | 50 Mbps up | 100 Mbps up | 250 Mbps up | 500 Mbps up |
|---|---|---|---|---|---|
| 1 TB | 3.7 days | 1.9 days | 22 hours | 9 hours | 4.5 hours |
| 2 TB | 7.4 days | 3.7 days | 1.9 days | 18 hours | 9 hours |
| 5 TB | 18.5 days | 9.3 days | 4.6 days | 1.9 days | 22 hours |
| 10 TB | 37 days | 18.5 days | 9.3 days | 3.7 days | 1.9 days |
And that's the optimistic version. Real uploads run below the rated speed: other devices share the connection, providers deprioritize sustained uploads, your Mac needs to stay awake for the duration, and many "gigabit" plans are gigabit down but 40 to 100 Mbps up. Cable plans are especially asymmetric. If your plan says 500/20, the number that matters for backup is 20.
For comparison, the same transfer to local storage:
| Destination | Realistic sustained speed | Time for 1 TB |
|---|---|---|
| External NVMe SSD (USB 10 Gbps) | 700 to 900 MB/s | 20 to 25 minutes |
| External SATA SSD | 400 to 500 MB/s | 35 to 45 minutes |
| External hard drive (HDD) | 150 to 250 MB/s | 1 to 2 hours |
A drive you bought for around a hundred dollars outruns your internet connection by two orders of magnitude. That gap is the entire argument for local-first.
Why cloud-first backup breaks down for footage
The initial upload is only the first problem. Three more show up after it:
Ongoing churn re-uploads constantly. Footage libraries aren't static. Every card you ingest adds hundreds of gigabytes, and every one of them has to crawl through the same upload pipe. A shoot that produced 400 GB on Saturday is still uploading on Wednesday. Until it finishes, that footage has fewer copies than you think.
Restore is the same math in reverse, plus fees. When a drive dies, you need the data back now. Downloading 5 TB at 250 Mbps takes about two days, and depending on the provider you may pay egress on every gigabyte. We covered the cost side in detail in the B2 vs Wasabi vs R2 comparison.
"It's in the cloud" hides a single point of failure. One account, one password, one billing hiccup. That's the argument we made in cloud storage is not a backup, and it applies double when the cloud copy is your only copy because the upload never caught up.
None of this makes cloud useless. It makes cloud a poor bulk-storage tier for people who generate terabytes, which is exactly what shooting video does.
The local-first setup that protects terabytes in hours
The structure is standard 3-2-1, with local drives doing the heavy lifting:
- Working copy on your Mac or editing drive.
- Two external drives with full verified copies of everything. Two, because a single backup drive means one failure leaves you with no backup. Big HDDs are the economical choice here; speed matters less than capacity for a backup tier that runs in the background. Our external drive guide covers specific picks.
- Cloud for the irreplaceable subset, which is the next section.
One of the two drives should live somewhere else: your studio, your home, a trusted friend's place. Rotating a drive offsite once a month covers the fire-and-theft scenario people buy cloud backup for, without pushing 10 TB through a residential uplink.
The failure mode of this setup isn't technical, it's human: copies drift out of date because syncing three destinations by hand is tedious. That's a solvable software problem, covered below.
Where cloud still earns its place
The subset worth uploading is small and precious: selects, final exports, project files, and the one shoot that can never be repeated. For most editors that's 5 to 10 percent of the library.
The math changes completely at that scale. Take a 10 TB library where 500 GB is genuinely irreplaceable: at Backblaze B2's $6.95 per TB per month, that's about $3.50 per month, and the initial upload finishes overnight instead of over weeks. Full pricing comparisons are in our storage cost breakdown.
This split also matches how loss actually happens. Drive failure takes bulk footage, and your second drive covers it. Fire, theft, or a bag left in a taxi takes everything local, and what you truly need back is the client deliverables and the raw selects, not 9.5 TB of B-roll alternates.
How to run this without babysitting it
Manually keeping two drives and a bucket in sync is where good intentions go to die. This is the part Tusk automates.
You create a project per job (one project maps to one folder), attach your backup destinations (external drives, Google Drive, or S3-compatible storage like B2), and Tusk syncs every change to all of them in the background, in parallel. Every transfer is verified with a BLAKE3 checksum before a copy counts as safe.
Two details matter specifically for large libraries:
- Per-file, per-destination status. Tusk's file table shows exactly which files have verified copies on which destinations, including drives that are currently disconnected. "Did the second drive get Saturday's shoot?" stops being a memory exercise.
- Deletion is gated on verified copies. When your editing drive fills up mid-project, Tusk will only delete local files that have a verified copy on every backup destination. Freeing space stops being a leap of faith. We wrote more about that workflow in freeing up space without losing footage.
To be clear about what Tusk doesn't do: it can't make your upload faster. Physics owns that. What it makes practical is the selective part, running full copies to fast local drives and a small verified subset to cloud, without you tracking any of it by hand.
What about a NAS?
A NAS can replace one of the external drives if you already run one, and it adds its own tradeoffs around cost and complexity. We covered that setup separately in the NAS backup workflow guide. The bandwidth logic in this article stays the same: your local network is fast, your uplink is not, so the NAS is a local tier, not a cloud substitute.
FAQ
At a sustained 50 Mbps upload speed, 1TB takes about 1.9 days of continuous uploading. At 100 Mbps it's about 22 hours, and at 25 Mbps it's 3.7 days. Real-world times are usually longer because connections rarely sustain their rated upload speed, and your Mac has to stay awake for the entire transfer.
Keep full verified copies on two external drives and store one of them offsite, rotating it regularly. Copying 1TB to an external SSD takes 20 to 45 minutes versus days for a cloud upload. Use backup software that verifies each transfer with a checksum and tracks which drive holds which files, so the two copies don't silently drift out of sync.
One external drive is not enough: if it fails, you have no backup left, and drives fail without warning. Two independent drives cover drive failure, and keeping one offsite covers fire and theft. Adding a small cloud tier for irreplaceable selects and deliverables covers the rest without uploading the whole library.
For terabyte-scale libraries, back up a subset: selects, final exports, project files, and unrepeatable shoots, typically 5 to 10 percent of the total. Bulk B-roll and alternates are cheaper and faster to protect with a second local drive. A 500 GB cloud subset costs around $3.50 per month at Backblaze B2's $6.95/TB rate and uploads overnight, while a full 10 TB library would take weeks to upload and cost around $70 per month.
As a rule of thumb, divide your monthly new footage by what your connection can push per day. A 100 Mbps uplink moves about 1TB per day flat out. If you shoot 400 GB per week, that's manageable; if you shoot 400 GB per shoot day, several times a week, the upload never catches up and local drives have to carry the bulk.
Yes. A Tusk project can have multiple backup destinations, mixing external drives, Google Drive, and S3-compatible storage like Backblaze B2, and it syncs changes to all of them in parallel in the background. Every file transfer is verified with a BLAKE3 checksum, and the file table shows which destinations hold a verified copy of each file, including drives that are currently unplugged.