Surveillance of places, people, inventory or actions can be achieved through the use of Closed Circuit Televisions (CCTV) systems.
A CCTV system consists of one or more video cameras in a ‘closed circuit’ which is not intended for public broadcast, but for selected users.
The design and application of a CCTV system is not always the easiest process. There are many factors that have to be taken into account;
» Technical specifications
» The application and requirements
» The physical constraints
With ever increasing product ranges and types of CCTV systems available in the market place, and technology constantly evolving to optimize performance, functionality and use, it is suggested to speak to a CSS Installation Consultant who would advise and customize the best solution within your projected budgets.
Many years ago there were only a few types of CCTV cameras in the market utilizing ‘Tube’ technology - nowadays there is diversity with multiple brands and product types relating to the different usage and applications.
Today most cameras utilize a computer chip called CCD (charged couple device), discarding the need for the tube. CCD converts light into an electrical signal, which is then processed by the camera electronics and converted into a video signal output that can either be recorded or displayed on a monitor producing high sensitivity and resolutions.
Digital signal processors (DSPs), increase the flexibility of the security cameras and also enhance the quality of the colour images they produce. A DSP is essentially a computer microchip or chipset, which allows the camera to process and manipulate video images.
Premium DSPs provide backlight compensation, video motion detection, remote set-up, built-in character generator, on screen menu displays and many other functions aimed at improving surveillance efficiency.
The combination of DSP and CCD technology has seen an improvement in image quality in most CCTV systems
Colour cameras are preferable from an evidential point of view; if the lighting is good then colour cameras should be your No.1 choice. However mono cameras work down to lower light levels than colour cameras and are normally slightly less expensive.
From low definition board cameras to high resolution, low light cameras such as those manufactured by Sony and JVC, CSS can specify and install the correct type for your application.
The definition for colour high resolution is anything over 752 x 582 pixels (PAL) with more than 460 TV line (TVL) resolution. Hi-res colour cameras require high-resolution monitors, recorders and other related products to achieve the high-resolution image display
These cameras display the images in black and white with all shades of grey.
Camera with circuitry able to be mounted into multiple casings. They may be mounted in a variety of ways in almost any application.
An ingenious solution to the problems caused by low light levels, these cameras produce colour images during the day, but as night approaches and light levels fall, they switch to a monochrome format to take advantage of its ability to produce clearer images in the dark.
Pan, Tilt and Zoom …… Full function cameras are fitted to motorized mountings which allow controlled pan and tilt of the camera, thus allowing it to view a wider area. Often these pan and tilt cameras will also be equipped with motorized lenses which allow controlled zoom in and out, thus allowing not only the scene to be changed but also the level of detail in the scene.
There is a camera inside a vandal proof plastic dome casing with omni directional bracket. No pan-tilt-zoom is possible with the standard dome. However high-speed dome cameras can now monitor 360 degrees.
These are ever increasing in popularity due to their outstanding performance and compact dimensions. Simple joystick control of all functions
Security camera resolution is a measurement of the security cameras clarity. A security cameras resolution is determined by the number of horizontal video lines (like 400 or 430 lines) that the security camera needs in order to reproduce the desired image. The higher the resolution number, the sharper the image will be. Although resolution is important when considering which security camera to purchase, the quality of the security cameras components is much MORE important.
Lux (1/10 of a foot candle) is a standardized method by which to measure a security camera's sensitivity to light. The lower the number, the less light it will take to reproduce a clear image. For example: A security camera that sees down to 1 LUX, means it generally has the ability to see an image during early evening hours or just before dusk. A security camera that's down to .1 has the ability to see an image in let's say, a well lit parking lot. A rating of .05, the ability to clearly view an image in a dimly lit area at night. A .05 image can usually enable a security camera to actually see better than the human eye at night!
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Surveillance Cameras
