Introduction to Closed Circuit TV
From a single camera and monitor to complex video surveillance systems with hundreds of cameras, multiple operators, and digital recorders, closed circuit television (CCTV) systems can provide security for a wide range of businesses.
A good closed circuit TV system can make your business safer, more efficient, and less prone to theft and accidents.
While the most basic closed circuit TV setup - a single camera connected directly to a monitor and recorder - could help security in some cases, it is unlikely to be enough for most businesses. Most situations call for multiple cameras. In some cases, you may even want a movable camera to cover a large area. Before starting to compare systems or choose potential vendors, sit down and consider your video surveillance needs carefully.
First, consider what you want to monitor. General comings and goings? Vehicles? Do you want to see faces, merchandise, crowds? Once you decide what you want to see, choosing components will become easier.
Next, decide what picture quality you need. Quality can refer to both how detailed the image is and how fast the frame rate is. Lower resolution and slower frame rates mean blockier, jerkier images, but let you record for much longer periods of time. Higher resolution closed circuit TV cameras and recorders are more expensive, but give you more detail.
One decision that's easier than it used to be is color or black and white: go with color. There's very little price difference any more, and color pictures can make identification much easier. Even the advantage that B&W cameras used to have - that they function better in very low-light situations - has been eclipsed by newer color cameras that switch to B&W mode under low light.
The price of your system will vary considerably, depending on the lenses, housings, and installation options you choose. A very rough rule of thumb to use for pricing a complete, installed system is $500 to $1000 per camera, plus the cost of your recording device.
Recording
Recording is essential to the effectiveness of any closed circuit television system. Without recording, you need to have an employee watching a monitor at all times - hardly a cost-effective solution. And even if you spot suspicious activity, without a recording, you have nothing to use in court.
Only a few years ago, the universal solution was the familiar VCR. However, the introduction of digital video recorders (DVRs), which record onto hard drives instead of tape, has dramatically changed the situation. DVRs offer so many advantages over VCRs that they have rapidly taken over as the closed circuit TV recording solution of choice.
- Saved images last longer on DVR
- DVRs can instantly jump to any point in the recording
- DVRs can play and record at the same time
- You can set the DVR to automatically increase the recording quality when it detects motion
For businesses that do not want to constantly change tapes, DVRs are definitely the way to go. While security VCRs usually offer a time-lapse mode that lets them record for long periods of time, the resulting images are not a good record of events - they record only one snapshot every eight seconds. To get higher quality, you need to change tapes every day or more often. DVRs, on the other hand, can record for weeks or even months.
DVRs are considerably more expensive than VCRs, which is their only major drawback. DVRs generally start at $800 to $1500 and get more expensive the more memory and inputs you add. Good time-lapse VCRs designed for security use start at $300 to $400 and go up to $600 or more. (Regular household VCRs can't stand up to the constant use that security VCRs get.)
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