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A follow-up to my question.

At this point it appears that I did not crimp the connectors correctly. After the connectors were crimped properly, the cameras were detected and (still under testing) did not drop. However there is something weird here. I'm seeing a difference of upto one (1) second between the timestamp of the connected cameras.

The System Time on the NVR was setup when it was first powered on - so I imagine the time should be identical. At present the system is not connected to the internet though eventually it will be.

For instance,

  • Channel #1 shows a time of 071622,
  • Channel #2 shows a time of 071621.
  • Channel #3 shows a time of 071623

Should all channels on a PoE switch have the same timestamp? Could latency be the cause seeing as atleast device has a cable run of nearly 150 ft?

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    I'm not sure how the switch would have much to do with the timestamps. Where are these timestamps coming from? Are these timestamps on a DVR? On a big screen showing thumbnails of all the cameras? Commented Jun 8, 2022 at 1:56
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    The timestamps are rendered on the screen showing thumbnails, yes.
    – Everyone
    Commented Jun 8, 2022 at 2:05
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    I’m voting to close this question because this question does not appear to be about home improvement within the scope defined in the help center.
    – FreeMan
    Commented Jun 8, 2022 at 11:43
  • VTC - This is additional material that belongs edited into the original question. Not sure that that question is about Home Improvement either.
    – gnicko
    Commented Jun 8, 2022 at 21:50
  • I’m voting to close this question because it is additional information that needs to be added to an original question not a "stand-alone" question.
    – gnicko
    Commented Jun 8, 2022 at 21:51

2 Answers 2

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The timestamp doesn't come from the PoE switch. Without having any experience with your particular hardware, I'm guessing that the cameras get their clock via NTP either from the internet or your NVR.

You should check the camera and NVR documentation or consult a community that supports them.

It also occurs to me that you might be experiencing variable latency in the video processing and display pipeline, and the camera clocks are actually in sync.

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  • Thank you, that sounds about right. I've updated the description above.
    – Everyone
    Commented Jun 8, 2022 at 2:06
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The cameras each have their own clock. They usually sync their time via NTP, but that requires an internet connection. Some DVRs run their own NTP server the cameras can sync with, but not all do that.

You need to set the time on the camera itself.

Latency and cable length should not be factors in this. The latency on even the longest cables will be far less than 1 video frame.

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