CCTV COMMISSIONING · 19 SEPTEMBER 2026

CCTV time synchronization and evidence export: a commissioning worksheet

A CCTV system can record clear video and still fail an investigation if cameras, recorders and operator workstations disagree about time, or if exported evidence cannot be opened and traced. Time and export checks should therefore be part of commissioning, not an afterthought.

Define one approved time source

Record the approved NTP source, time zone, daylight-saving policy where applicable, and the devices expected to use it. Include cameras, NVR or VMS servers, access-control panels, operator workstations and any analytics or event servers that contribute timestamps.

The AXIS OS web-interface documentation exposes NTP synchronization state and the time remaining until the next synchronization. This is a useful commissioning principle for any system: record observed synchronization status rather than only recording the configured server address.

Test time at camera, recorder and client

Choose a visible reference clock and compare it with the camera overlay, recorder timeline and operator workstation. A small sample from one camera is not enough for a distributed system. Test cameras from different switches, buildings, fiber zones and recorder groups so network or configuration boundaries are represented.

After a controlled restart of selected devices, confirm that time synchronization returns without manual correction. If a camera continues recording locally during a network interruption, verify how the VMS handles the recovered footage and timestamps after reconnection. Record the behavior actually witnessed instead of assuming it from product capability.

Use an event to prove cross-system alignment

Create an approved, harmless event that can be seen by more than one source, such as a person walking through two camera views or an authorized access event at a monitored door. Compare the event time in each recording and, where integrated, in the access-control or alarm log. The acceptance limit should be agreed by the owner before testing.

This matters because investigations often combine camera views, entry records and operator actions. If their clocks disagree, the sequence can appear incorrect even when each individual system is functioning.

Export a real evidence sample

Export a short clip that crosses the chosen event. Record the selected camera, requested start and end times, actual exported duration, file format, player requirement, visible timestamp behavior and file size. Open the export on a separate approved workstation, not only on the recorder that created it.

ONVIF Profile T defines standardized capabilities for advanced video streaming and associated metadata. Product conformance and export behavior still need to be checked for the exact camera, recorder and VMS combination being delivered. A label or compatibility claim does not replace a witnessed export test.

1. Playback: verify the clip opens, plays at normal speed and allows the required camera view to be identified.
2. Timing: compare displayed time with the recorder timeline and the commissioning event record.
3. Integrity: preserve any native player, verification utility, signature or checksum supplied by the system and document how it is used.
4. Audio and metadata: where these are in scope and legally approved, verify that they are included and remain aligned with video.
5. Chain of custody: record who created the export, when, from which system, where it was copied and who received it.

Keep the handover record usable

The owner should receive the approved time-source list, synchronization status for sampled devices, the cross-system event results, export procedure, player or verification requirements, evidence naming convention, retention and access responsibilities, and all unresolved exceptions. Credentials should be transferred through the owner's secure process, not written into the general handover report.

Buyer acceptance checklist

• One approved time source and time-zone policy is documented.
• Camera, recorder and operator-client clocks were compared.
• Synchronization recovery was checked after a selected restart or interruption.
• A cross-camera or cross-system event was used to verify sequence alignment.
• A real clip was exported and opened on a separate workstation.
• Native player, verification and metadata requirements are documented.
• Evidence handling ownership and access are assigned.
• Exceptions have owners and closure dates.

Related reading: use the CCTV recording retention and storage worksheet to validate capacity and playback policy. For project scope, see CCTV and surveillance services.