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Viewer & Quick Look

DCommander gives you two fast ways to inspect files without breaking flow:

  • Quick Look — instant, lightweight previews
  • Internal Viewer (F3) — detailed inspection in Text/HEX/Media modes

Legend: ⌘ Command · ⌥ Option · ⌃ Control · ⇧ Shift · ⏎ Return · Space

Quick Look (fast preview)​

  • Select an item and press Space. Press Space again to close.
  • Works for common images, video, audio, PDFs, and documents.
  • Supports multi-select: arrow through selected items while Quick Look is open.
  • From the context menu (right-click), choose Quick Look as well.
note
  • If Alternate Spacebar action is enabled, Space may toggle selection instead of Quick Look.
    Configure your preferred behavior in Preferences › Navigation/Keyboard.
  • On remote shares, Quick Look may fetch enough data to render a preview. Very large files can incur network round-trips.

Internal Viewer (F3)​

Press F3 (or choose View from the context menu) to open the built-in viewer.

Modes​

  • Text — UTF-8/ASCII text with basic navigation.
  • HEX — Byte-level inspection for binaries; useful for signatures and headers.
  • Media — Quick playback/preview for common audio/video types.

Switch modes from the viewer’s toolbar (where available) or via a menu.

External viewer (optional)​

Prefer a different app for viewing? Set an external viewer in Preferences › Operation › External Apps. From then on, F3 can open the external app instead of the built-in viewer.

Compare: Quick Look vs Viewer​

FeatureQuick Look (Space)Internal Viewer (F3)
Launch speedInstantFast
Deep inspectionLimitedText/HEX/Media
Works across remotesYes (previewed)Yes (subject to access)
Multiple filesYes (arrow through)One at a time (open next/prev if supported)
External app routingVia “Open With”Configurable via Preferences
tip

Use Quick Look for “is this the right file?” and Viewer for “what’s inside exactly?”.

Power tips​

  • Spot-check after copy: In the destination pane, select a few files and press Space to confirm content and integrity.
  • Preview before batch actions: Combine Search results with Quick Look to verify matches before F5/F6.
  • HEX for headers: Use F3 → HEX to confirm magic numbers (e.g., 89 50 4E 47 for PNG).
  • Keyboard flow: Keep one hand on arrows and Space/F3—you can preview dozens of files in seconds.

Performance considerations​

  • Large media on network shares: Quick Look may fetch partial data; very large videos over high-latency links can stutter. If so, copy locally first, then preview.
  • Gigantic text/binaries: The built-in viewer is optimized for quick inspection, not full editing. For huge logs, consider opening with your editor (F4) and tailing.
  • Many small previews: Rapid-fire Quick Looks on a remote tree can add round-trips. Use Search to narrow first, then preview.

Troubleshooting​

  • Quick Look shows “No Preview”
    The file type may lack a generator on your Mac. Try F3 (Text/HEX) or Open With a dedicated app.
  • Viewer can’t open a file
    Ensure you have read permission; try Refresh (⌘R) if the file was just created or replaced.
  • Space toggles selection instead of preview
    Disable the Alternate Spacebar action or remap in Preferences › Navigation/Keyboard.
  • Remote preview is slow
    Copy a subset locally, preview there, or preview fewer/lighter files (e.g., thumbnails).