When time is adjusted backward, it changes from Daylight Saving Time (DST) to Eastern
Standard Time (EST).
The timeshift from DST to EST occurs at 2:00 am. Before 2:00 am,
Security
Center uses the DST (UTC-4). Starting from 2:00 am,
it uses the EST (UTC-5), as shown in the following table:
| |
DST |
Time change |
EST |
| Local time |
12:00 am |
1:00 am |
2:00 am = 1:00 am |
2:00 am |
3:00 am |
| Offset (hours) |
-4 |
-4 |
-5 |
-5 |
-5 |
| UTC |
4:00 am |
5:00 am |
6:00 am |
7:00 am |
8:00 am |
Because the time was adjusted backward, the following behaviors can be observed when playing
back video or exporting archives:
- The time shifts back by one hour in the timeline. After 1:59:59 am, the displayed time
falls back to 1:00:00 am.
- The end time of a video sequence can be earlier than the start time.
- Exporting archives between 1:00 am and 2:00 am always includes an additional hour of
video. For example, when exporting archives from 1:50 am - 2:00 am on the night of a
timeshift, the exported sequence includes 1 hour and 10 minutes of video because the query
includes video from 5:50 am - 7:00 am UTC.
To prevent the time from shifting back by one hour during video playback, or to export
video without an extra hour of footage, you must
configure Security
Desk to use UTC.
After exporting the sequence, you can revert to the previously configured time zone to view
the sequence relative to your local time reference.
