GUIDE TO CCTV
There are a vast range of CCTV products and prices to choose from in the marketplace but little information to help discriminate between them. Here are some examples.
A camera described as good in low-level light will often not produce images at night unless there is additional lighting. There may be no explanation or qualification of the term low-level light.
Wireless cameras can be fitted in minutes as there are no cables to run back to your TV or monitor. However, the cameras still require a power source and while battery power is convenient the consumption is great giving a working time of less than 24 hours (as low as 2 on some products tested).
Wireless connectivity is nevertheless very useful for some applications as described later.
There are plenty of professional CCTV installers who will give you a site survey and recommend appropriate products but, of course, you pay for this service. Modern technology has now made CCTV products much more affordable and they can be very easy to fit for the average DIY person. This guide will help you choose the correct products and show some simple methods of fitting complete systems to domestic and commercial properties. DIY CCTV Systems can easily be fitted by people with moderate DIY skills.
Choosing a Camera Specification
The main criteria of a camera’s performance are its sensitivity and resolution. Secondary considerations are colour or monochrome and indoor or outdoor suitability.
Sensitivity is the camera’s ability to respond to light levels. Resolution defines the amount of picture detail in the image produced by the camera.
The traditional CCTV camera has a very industrial style and, therefore, many people would not find this suitable for fitting to their homes or shops.This traditional style is actually a housing that is designed to keep the camera dry and within the recommended operating temperature. Thermostatic heating elements within the casing also reduce condensation and misting.
These types of top-end cameras are usually specified without a lens, this being chosen to give the required focal length and field of view. Motorised pan and zoom lenses allow an observer to follow or move in closer to the person or object in view.
We can supply these types of cameras to those of you who do not find the price prohibitive.
Fortunately, for those of us with more down-to-earth budgets modern technologies now allow the production of cameras with excellent performance. There are two common types of CCTV cameras, CMOS and CCD (see glossary of terms). CMOS based cameras are generally cheaper but do not produce as clear or sharp images as CCD cameras. There is little point installing a CCTV camera if it is incapable of allowing you to easily identify who or what is being captured and recorded. CCD cameras provide pin-point clarity and should be specified wherever possible.
The KT&C, Everfocus and Concept camera range, in general use the Sony CCD chipset. Beware of competing products that do not state whose chipset is used.
Integrated cameras and lenses often referred to as “bullet cameras” are sealed to prevent ingress of moisture. The sealing is so good that they can be permanently immersed to some considerable depth in water if required.
Bullet cameras do not need a heater and their small size makes them highly suitable for fitting to domestic and commercial properties. It is not possible to make adjustment to these cameras because they are permanently sealed. Most of the bullet cameras are fitted with a 3.6mm lens which gives a 72 deg angle of view which is suitable for most domestic and small commercial properties. Please contact us if you require alternatives.