What is CCTV? Why is there a need for CCTV?

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CCTV (Closed Circuit Television) is a visual surveillance technology designed for monitoring a variety of environments and activities. CCTV systems typically involve a fixed communications link between cameras and monitors. Today, CCTV cameras are widely used in a variety of circumstances, they are used in

1. Assisting the police and security organizations in their investigations,

2. Schools, businesses, industries and some other premises in order to monitor the activities taking place.

3. Shopping malls, boutiques, bus terminals, MRT stations, underpasses,   Automatic Teller Machines ATM, sensitive government buildings, private estates and even extending its application to red-light districts, in an attempt to monitor and deter illegal activities and etc.

 

 

 

What is NTSC and PAL system?

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NTSC stands for National Television Standards Committee. It is the color video signal television. Standard: 525 lines, 60Hz. PAL stands for Phase Alternate Line. It is the color video signal television. Standard: 625 lines, 50Hz.

 

 

 

How to choose a suitable CCTV camera for our needs?

 

When choosing the correct CCTV camera for you application as below followed.

a) Location: Indoor or outdoor application

b) Requirement for day and night surveillance

c) The angle of view requirement. Wide angle coverage or a narrow field of view is required

d) Budget

 

 

 

What is focal length and How does focal length affect angle of view?

 

Focal length is measured how long distance from object to camera.           

Focal length is measured in mm. A short focal length (e.g. 3.6mm) represents a wide angle of view while a long focal length (16mm) represents a narrow angle of view.

 

 

 

What camera housing to use in outdoors and at what IP rating?

 

Camera housings are of various shape and sizes. Different housing comes with different UP rating, from dust proof to all weather rating. This system is governed by a number of European and British standards

IP55,

• Protected against dust – limited ingress

• Protection against low pressure jets of water from all directions – limited ingress permitted

IP65

• Protected against dust – limited ingress

• Protection against low pressure jets of water  from all directions – limited ingress permitted

• Protection against high pressure water from all directions – limited ingress permitted

 

 

What is CCTV DVR?

 

DVR is abbreviation for Digital Video Recorder, it main work is to compress images recorded from the cameras into a particular image compression format and store them.

 

 

 

 

What is the difference between a PC-based DVR and an Embedded DVR?

 

A PC-based DVR is basically a personal computer that has been modified with hardware and software to work as a DVR.

An embedded DVR is a video recording machine that has been manufactured specifically to record video input from CCTV cameras.

 

 

 

What features should I look for in a CCTV DVR?

 

All DVRs are different. There are various factors to consider when purchasing a DVR besides price comparison. The basic and most important factors to consider are

 

i) Number of cameras supported, i.e. number of video inputs

 

ii) Recording at how many frames per second (fps)

 

iii) Compression technology used

 

iv) Hard disk space, number of hard disk it can support

 

v) Network connection / remote viewing capability

 

vi) Motion detection or scheduling recording functions

 

vii) Video backup means, by USB, CD, DVD or other means.

 

viii) Easy and comprehensive search capabilitie

 

 

 

What is the maximum length I can pull my cameras away from the DVR?

 

Using RG59 Coaxial cable, the maximum distances approx 600 feet away from the DVR and up to 1,000 feet using RG6 Coax. For longer distances, a video amplifier should be used.