CCTV Systems and Camera SelectionCamera

The choice of camera and lens are the most important factors when you’re designing CCTV systems for security. Choosing the right lens and camera will ensure that you get the most value from the CCTV camera that you choose. Let’s walk through the most important points in lens and security camera selection to help you design the best CCTV security system for your use.

CCTV Camera Lens Types

CCTV security cameras come in three basic lens types: fixed, varifocus and zoom.

A fixed lens can not be adjusted. It’s best for applications where you only want to survey from one angle and have no need to widen or narrow your viewing angle.

Varifocal lenses are adjusted manually. Generally, you’ll set it and leave it at that setting. The range of length is usually fairly narrow, and will vary widely depending on the security camera manufacturer. Generally, you’ll find lenses in ranges from about 2mm to 50mm.

Zoom lenses can be adjusted through the CCTV security system as you view the output on a monitor. You’ll generally find zoom lenses on Pan, Tilt and Zoom (PTZ) CCTV systems. To determine the size lens you need, you’ll need to know the width of the scene you want to observe and the distance from the camera to the scene. The basic calculation to decide the lens length is:

distance/width * 4.8 = focal length

In addition to focal length, your security camera will have any number of other adjustable settings, including back light compensation, auto iris, electronic shutter, automatic white balance and many others. Before you choose cameras for your CCTV systems, get to know what the settings do and decide which are important to you so that you can be sure to get a security camera that fits your needs.

CCTV System Information

Another one of the key differences among CCTV security system types is the way that the camera connects. Analog security camera CCTV systems are usually connected to the monitor by coax cable or another type of wire. For decades, analog systems were state of the art – and your only real choice. While they deliver high quality picture with no concerns about interruptions, they also require hard installation, generally by a professional who can run the wires. Once the cameras are installed, you ability to reposition them is very limited.

The more popular option today is an IP camera. An IP CCTV camera connects on a network, just as a PC or printer does. This provides a great deal of flexibility in positioning, because the cameras don’t have to be connected to the system by a wire.

Those are the absolute basic things you need to know when choosing among the many CCTV systems available. The more research you do, though, the better and more informed choice you can make and the better your choice will be for your needs.