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Guide to Closed Circuit TV (CCTV)

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.

Time Lapse, VCR's, DVR's, NVR's ...
it's time to go on the record...

How to get the best from a record system - continued

On Monday it can then be changed back to 24 Hour to double the number of images recorded per second. For some applications, particularly where archiving is not required, you can select the ‘Repeat Record’ function, and the machine will automatically rewind at the end of the tape, and then start recording again, from the beginning. It should be mentioned that this function should only ever be used as a last resort, and not simply as a choice of convenience.

In some situations, it is well worth using the alarm input to switch a recorder from Time Lapse to 3 Hour normal record speed; a typical example might be if the panic button is pressed in a bank or jewellery store.

This will provide continuity in recording, with loads more images during the alarm period (and also reasonable quality audio if a covert microphone is installed). If at all possible, try and avoid ‘alarm triggered recording’ on its own, as without the continuous before and after bits, the evidence may not prove to be irrefutable in court.

Always look carefully at the picture and identify the ‘dead area’ where it is most sensible to place the Time and Date display; do not leave it overlaying the key location where suspects are most likely to present themselves to camera, or you might just end up looking at man Friday!.

Also, if possible switch off unnecessary bits of captioning, such as the ‘alarm count’ display, as the less clutter there is on the screen, the better the view of the action.

If the machine is fitted with audible alarms, it may well be worth switching on the ‘tape end’ or ‘record fail’ warnings. It perhaps goes without saying, but if you are using a VHS recorder always buy the very best quality (EHG) branded E-180 tapes (SE-180 for S-VHS), and replace them regularly.

Although tapes do wear with use, “the tape was worn out” is perhaps the most rubbish excuse commonly used, to cover a multitude of operational sins; in practice, if you were to record someones face two hundred times on the same tape (at least let them go to the toilet now and again!), then even allowing for tape degredation, on playback you should still be able to identify them beyond reasonable doubt.

Continued >>

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