Kai Mallari's Notes'

EC - Disk Full Recovery

3 min read

Disk Full Recovery

Symptom: Capture One errors on capture (“Cannot write to disk”), or the system becomes extremely slow. Finder may show a “Disk Almost Full” warning. Root Cause: Capture destination drive has insufficient free space for new RAW files and Capture One’s temporary/cache files. Referred from: DIT Triage - C1 Crashed, DIT Triage - Tether Dead, DIT Triage - Slow Performance

Diagnosis

  1. Check remaining disk space: Apple Menu > About This Mac > Storage. Or in Terminal: df -h.
  2. If the capture drive has less than 1-2 GB free, this is the problem.
  3. Note: Capture One needs free space for both the RAW files AND its preview cache and temporary files. A drive that appears to have 5 GB free may still fail if C1’s cache is growing.

Fix

Immediate Response (buy time)

  1. Stop shooting. Tell the photographer to hold. “We need 2 minutes — the drive is full.”
  2. Check space: Apple Menu > About This Mac > Storage. Or in Terminal: df -h.
  3. Empty the Trash. Finder > Empty Trash. This is often the fastest way to recover 5-20 GB.

Free Space Quickly (in order of impact)

  1. Clear the Capture One preview cache:

    • Capture One > Settings > Performance > “Clear Cache.”
    • This can free 2-10 GB depending on session size. Previews will regenerate on demand (briefly slower).

  2. Delete old sessions or catalogs on this drive:

    • If the photographer has previous shoot sessions on the same drive, they may be taking up space. Confirm with the photographer before deleting anything.

  3. Delete large non-essential files:

    • In Terminal: du -sh ~/Desktop/* ~/Downloads/* | sort -rh | head -20 to find the biggest consumers.
    • Common culprits: old downloads, software installers, Time Machine local snapshots.
    • Delete Time Machine local snapshots: tmutil deletelocalsnapshots / (requires admin password).

Redirect Capture Destination

  1. If the internal drive is full, redirect to an external drive:

    • In Capture One: Session menu > the session’s Capture subfolder > right-click > “Set as Capture Folder” after creating a new folder on the external drive.
    • Or: Capture One > Session > change the Capture Storage location to the external drive.

  2. If all drives are full:

    • Capture to SD card in the camera (disable tethered capture, shoot to card).
    • Import from card between setups.

Prevention

  • Before every shoot: verify at least 2x the expected shoot volume is free on the capture drive. A typical calculation: (expected shot count) x (RAW file size) x 2 = minimum free space needed.
  • Use the largest available drive for capture. Internal NVMe is fastest.
  • Exclude the capture drive from Time Machine backups during the shoot.
  • Don’t use the capture drive for anything else during the shoot.
  • Include a disk space check in the pre-shoot setup checklist (see SOP_Photographer_Handoff).

Documentation

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