Time Synchronization

Overview

Nexus uses Unix-based timestamps combined with relative elapsed seconds to synchronize all signals. When you scrub the timeline, every panel displays the data corresponding to that exact moment. The UI formats time as a time-of-day display (HH:MM:SS) by mapping the absolute timestamps to wall-clock times.

How Synchronization Works

Every signal in Nexus carries an absolute timestamp (Unix time combined with the relative elapsed seconds from the experiment start). When you scrub the timeline or start playback:

  1. The timeline cursor moves to a new time value.
  2. Nexus finds the closest frame or data point for each visible signal at that time.
  3. All panels update simultaneously - images display the matching frame, graphs move their cursor, and annotation overlays refresh with the corresponding values.

Because all signals share the same absolute time axis, data captured by different instruments at the same moment is presented side-by-side.

Working with Signals from Different Sources

Nexus can load files from multiple instruments in the same session. As long as the instruments recorded timestamps using the same clock (or were synchronised beforehand), the signals will align automatically on the timeline.

If timestamps don’t align:

  • Signals appear at different positions on the timeline based on their recorded acquisition times.
  • You can still view them together; the timeline stretches to cover all loaded signals.
  • Use the Sync mode to manually align signals (see below).

Manual Time Offset

When signals from different instruments don’t share the same clock, you can align them manually using time offsets.

  1. Click the Sync toggle button in the timeline controls to enter sync mode.
  2. Drag a signal sparkline left or right on the timeline to apply a time offset.
  3. Hold Shift while dragging if you want snapping to note timestamps or other signal boundaries.
  4. Release to store the offset as a pending adjustment.
  5. Click Sync again to exit sync mode. Nexus then asks whether to apply or discard the pending adjustment, and whether to apply it to only this signal or the whole dataset.

Time offsets are saved as part of the project file. You can apply offsets to individual signals or to entire datasets.

For the best synchronisation, ensure all instruments are clock-synced before starting the experiment. DENSsolutions Impulse software records experiment date and time precisely for this purpose.