Welcome to the
"Coppers Corner"
section of
Doktor Jons

Guide to Closed Circuit TV


So would you like to play "Spot the CCTV Camera?". Eagle eyed visitors may recognise the profusion of street furniture, surrounding a single heritage dome camera keeping watch over part  of Londons' prestigious Oxford Street shopping area.
Doktor Jons CCTV Forum provides a unique location to discuss and exchange information on all aspects of video surveillance

A brief Anti Terrorist informative for organisations using
Closed Circuit Television, potentially for "Homeland Security"- cont.

6) If using tape, always make sure that recordings are logged and securely stored for an appropriate period (normally an absolute minimum of 14 days, with one month being the much preferred option), and that you are using absolute 'top quality' branded Extra High Grade (EHG - 180) video tapes for VHS machines and "SE-180" tapes for S-VHS recorders.
Wherever possible, try and avoid using E-240 tapes, as their thinner base material generally makes them less durable for punishing analogue 'Time Lapse' video recording. It's also important to make sure the recording equipment is correctly inspected and maintained.

7) Don't wait for tapes to wear out, but replace the cassettes at regular intervals, perhaps every six to twelve months depending on their usage.
This is particularly important for systems using recording multiplexers, as even slight stretching of the tape can mean that it becomes impossible to recover the recorded images.

8) Remember to check that any recorder Time, Date or Caption settings are programmed correctly.
If they're wrong, the recordings may not be acceptable for court use (they would be regarded as 'corrupted' data, under the U.K.'s Data Protection Act), oh and don't forget the all important (compliant) CCTV warning signs, if the DPA specifically applies to your installation.

(For more information on the DPA, look at
this page, and also this story).
It is also vitally important to make sure that any caption information is correctly positioned on the screen, so that it does not obscure any vital recorded information, such as a suspects face or a vehicle registration plate.

9) Where images are to be recorded for possible evidence, a video switcher, Picture in Picture (PIP), or Quad multiplexer unit should not really be used as they will all compromise the suitability of recordings.

Only a high quality full screen recording multiplexer (or quality built multi channel DVR / NVR) will guarantee that the maximum amount of information is recorded as clearly and efficiently as possible.

10) Don't forget to regularly check the overall quality of video recordings; ideally on a daily basis if possible.If the pictures, look 'unstable', the tapes may need changing or the machine may require a service; if they're dark and grainy make sure the camera / lens is set up correctly for the ambient light levels - you may also need to consider either improving the lighting, or replacing the camera with a more sensitive model.

11) Make sure that any outdoor camera housing windows or dome covers are regularly inspected, and carefully cleaned if necessary; dirt and grime can seriously affect the overall picture quality. In fact, a gentle wipe down of the monitor screen, can also dramatically improve image quality.

12) In certain situations, consider the old 'double deception' approach to camera installation.
If the situation warrants it (see CCTV
System Profiling), consider using proper dummy cameras as the primary visible deterrent, and covert or discreet high quality cameras for the evidential recording.
Before you dismiss the idea outright, why not take the
'Deterrent Test'.

Remember if you place the dummy camera within view of the working unit, there is always the possibility of capturing very clear evidential quality images, if the suspects try and 'disable' the dummy!
Final thought, CCTV isn't simply about producing pictures ..... but far more importantly, it's all about producing results - if you want to check the effectiveness of any existing CCTV cameras, have a look at the new
TRUSTED CCTV System improvement section or if you'd like a detailed report on an individual camera's technical efficiency, have a look at DJ's latest unique "VIPER" evaluation service.

Doktor Jon reports on CCTV and the London bombings >>
A CCTV image of the London Bombers - could it have been improved? >>
Doktor Jon reports on "The future for Forensic Surveillance" >>
For any further specific advice contact Doktor Jon >>

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TRUSTED - Target Recognition Using Surveillance Technology for Evidence and Detection - A campaign to improve the effectiveness of existing video surveillance security systems.

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