What is the best way to capture a video, which should be possible to time-align to absolute time (e. g. UTC.)? The required precision of time alignment should be comparable to the exposure time.
I noticed that there is possible to install the ntpd to the camera OS, which is a good base for timing. But I do not know how to mark the system time precisely to the video.
Also, I noticed that there is a time in the text overlay, It seems it always shows a time of around 17xxx seconds. But It is unclear for me which time is a zero?