Sometimes, time stamps appear on footage taken from security cameras. When this happens, several things that would be on real security footage timestamps are frequently missing from the televised vs.:
- The date the footage was taken. If the footage was taken at "12:00 PM" but not on any particular day, then either info has been edited out or someone is taping over tapes too frequently. In fiction, it may be omitted in an attempt to avoid literally dating the work.
- The camera location may not appear. Admittedly, when it does appear, it is likely to be in a form that would not be understood by laypeople. But if the security camera is located in a place with more than one of them, its tape should say which one.
- The time may be given in hours and minutes, but not seconds. Since the seconds aren't that much more trouble and help pinpoint spots on the tape, real displays normally include them.
This happens far more on British TV than in the US. American "security camera footage" tends to have either all the info (possibly pixellated, but there) or none of it. "None" is a legitimate display option, but it removes some of the cues that it is a security camera.
The Dodgy Time Stamp is applied in a different manner when referring to a television series. In this case (and especially in the Star Trek franchise), characters In-Universe can tell on careful inspection that it's dodgy. It's usually used to help the main characters detect forged log entries, forged security camera recordings, forged communications from (or relating to) a missing third party, etc.
If the time stamp displays SMPTE time code (frames 00-29 are displayed after the seconds) this is a variant of Magical Security Cam!