Although the application of CCTV security have not changed very much over the past years, the tools and equipment have significantly. Cameras became smaller, cheaper and better, but the major breakthrough happened in recording equipment.
Therefore many customers shopping for complete CCTV monitoring and recording systems are confused by such a verity of available products. Goal of this article is to guide buyers toward best possible and most economical type of CCTV equipment, based on intended implementation and requirements.
Selecting the right cameras.It is virtually impossible to describe all types of available ones in this short article. We will focus our attention on most popular and widely used camera types instead.
CCTV produce images using CMOS or CCD (Charge Couple Device) chips. Tiny, very low price CCTV cameras usually use CMOS technology, produce poor quality images and have very poor light sensitivity. Decent quality CCTV cameras use CCD technology. The size of the CCD chip is normally 1/4″, 1/3″ or 1/2″. As a rule of thumb, the larger the size, the higher the quality of the image produced and the higher the price. However, higher density 1/4″ and 1/3″ CCD chips can now produce as good an image as many 1/3″ or 1/2″ chips.
The number of TV lines in the security camera image is a measure of picture resolution (sharpness). The larger the number of TV lines, the better the resolution and hence, overall picture quality. Standard resolution camera may have 350-380 lines, over 400 TV Lines is generally considered good resolution while over 500 TV lines is considered high resolution. B/W chip cameras produce greater resolution and better light sensitivity, therefore suitable for use in dark areas where light conditions are poor most of the time.
On the other hand color cameras offer more realistic and natural picture. CCTV cameras
Professional grade cameras.
Have box type body with the ability to use different types and size of lenses. Exchangeable lenses enable this camera, to monitor objects from virtually any distance. Although for indoor use, they can be used for outdoor when combined with weatherproof housing. They are considered to be the most flexible and widely used by professionals for commercial installations.
Bullet cameras.
Bullet cameras are, as the name suggest contained inside bullet shaped housing.
Most bullet cameras are weatherproof and sealed without the ability to use different lenses. Great advantage of bullet camera is the small size and integrated design, some bullet cameras will even have infrared LED future built-in. simply LED light in infrared spectrum (not visible to human eye). This light will illuminate viewing area, making possible monitoring in complete darkness. This is great future, but it only works up to certain distance (usually between 10 and 50 ft. depending on model) Vary simple to install and estheticly designed, bullet cameras are great choice for residential and do-it-yourself installations where monitoring objects are within about 25ft from the camera location (with standard 3.6mm lens).
Board Cameras.
Board Cameras are basically fixed lens mounted on a circuit board. These cameras may be packaged in a small case (Mini Cameras) or dome (Mini Dome) or simply sold unpackaged, for mounting by the purchaser. Lenses in these are either of a normal industry aperture or a “pinhole” lens of very small aperture. Pinhole lens cameras are often called “spy” cameras and may be mounted in a concealed way for covert surveillance purposes. The most popular examples of covert board ones are smoke detector and motion detector cameras.
Since the lenses in board cameras are pre-mounted, have a fixed iris and are usually of a short focal length (i.e. wide angle), their flexibility of usefulness is limited. However, this type of camera can provide a low cost solution in the right situation, particularly in a home environment. We have shortly described most popular types of cameras, lets now discus, how and where they mite be used.
Professional types with C/CS mount lens attachment generally offer best performance and many important futures, like lens control output, Back Light Compensation and many more…
Distance from monitoring object to the camera is not an issue, that is why ability to select different lenses, based on location is so important. Installation is bit complicated and professional installation strongly recommended. We recommend this type of security cameras for commercial installations.
Most Bullet cameras in comparison, do not offer high resolution and lens selection flexibility, but are likely to be weatherproof, some will have infrared light built-in and most of all they are relatively easy to implement. They usually come with 3.6mm lens witch are considered to be suitable for most standard installations (good for covering small to medium size room or equivalent).
For larger rooms or longer distances, cameras with 6mm or higher lens may be required. They are great choice for any do-it-yourself installation.
Board cameras in contrast are widely used in covert camera installations, sometimes called Spy Cameras. Many are basically board ones with built-in transmitter. We are not going to go into wireless cameras right now, as this would be enough material for completely new article.
Board cameras are sold as plain circuit board, for integrating into hidden camera devices. They are also available in dome housing, as vary popular Dome Camera or integrated with Smoke Detector, Motion Detector, Exit Sign and so on. Most also come with 3.6mm lens although some will allow lens to be replaced.
Over the time, most practical design has been Dome Camera with its aesthetic appearance it blends into surroundings, especially with drop down sealing, great for use in stores, lobbies, gas stations and other public places. Practical solution for covert installation are also, Motion and Smoke Detector cameras, they are absolutely not substitute for your security alarm or fire protection. They should always be selected based on the location of the camera (inside/outside), distance from the monitoring object, light condition and budget.
When shopping for security cameras, customers are faced with the fact that they will need to select one or another recording device.
The days of well-known CCTV time-lapse recorder are almost over.
Although some customers still prefer this old fashioned recording solution, it is well worth to invest some extra money to purchase a good quality digital video recorder (DVR). Digital recorder transfers analog camera video feed into format, and stores it on hard drive. There are two major types of digital recorders on the market right now.
