Houston Analog Cameras

An Analog Camera system has a CCD sensor, this digitises the captured image so that it can be processed easily. However, before the video can be transmitted it must be converted to analog so it can be viewed.

In the traditional analog CCTV application, security cameras capture an analog video signal and transfer that signal over coax cable to the Digital Video Recorder (DVR). Each camera may be powered by plugging in the power supply right at the camera or by using RG59 Siamese cable which bundles the video and the power cables. The DVR converts the analog signal to digital, compresses it, and then stores it on a hard drive for later retrieval. Intelligence is built into the DVR to handle such things as scheduling, motion detection, and digital zoom. Monitors for viewing the video are connected to the DVR, or it can be set up to publish over an internal network for viewing on PCs. The DVR can also be set up to broadcast over the Internet and can add password protection and other features. When broadcasting over the Internet, the video for all of the cameras is transmitted as one stream (one IP address). Therefore, it is very efficient.

There are two popular analog standards in the world for television: NTSC (e.g. as used in North America and Japan) and PAL (used in many other countries, especially in Europe). There is also SECAM but it is not a common standard in CCTV world.

Pros
Analog Cameras take less time to install and require minimal setup and configuration, as a result they are much cheaper than other systems. The unit themselves are less expensive.

Analog Cameras require little maintenance basically once a week just to ensure that the cameras are recording properly and the footage is being stored in the DVR hard drive. One more great thing about analog cameras is that they are not connected to the main network hub which reduces the chances of bugs, virus or bandwidth limitation.

Analog Cameras work well with low light because of their CCD sensor that helps it to perform better. They also have built in infrared that can capture footage even in pitch black.

Analog Cameras are processed inside a DVR and not the camera itself so it can be viewed live without any lag.

Analog camera parts will work alongside any standard DVR, which makes upgrading your device easy.

Cons
Analog Cameras are typically less capable than digital cameras to analyze and image. They also require the use of DVR to record images, Analog cameras can't record the images itself.

Analog Cameras have lacking features such as zooming in on an area. This can be a major flaw if you want to zoom in to identify a person.

If you have a wireless surveillance using this system, then you might run into interference problem due to signal crossover and someone else can access this signal and retrieve information.

Analog Cameras does not cover a broad range, so if you need to observe a wide scope of area, then Analog Cameras may not be for you.

Analog Vs IP

• Analog CCTV products are at this point in time still cheaper than their IP counterparts – NVRs can be twice as expensive as a DVR for example. The installation of an analog surveillance system can also be less expensive because they are quicker to install with minimal network set-up and configuration. However in some situations a single IP camera can be installed in the place of a number of Analog CCTV cameras.

• Because an analog system is not attached to the business or home network it won’t be at the mercy of network issues. Large file sizes, limitations to the bandwidth, viruses or too many devices trying to use the network (congestion) are just some of the challenges facing the installation and ongoing maintenance of an IP system.

Depending on the environment an analog security camera may perform better than an IP camera in the same position. Situations where this may occur include:

• Low light: The CMOS image sensors normally used in IP cameras deliver great HD resolution but do not handle low light very well. Some IP cameras will produce a grainy picture at low light (which also uses up bandwidth and storage space because it is interpreted as motion)2. Many analog cameras use a CCD image sensor which has much better low light performance.

• Darkness: Most analog surveillance camera include in-built IR (infrared) that allows the camera to record images even in complete darkness. While IP cameras will record down to a very low level of light if they need to record in zero lux separate IR illuminators will need to be installed.

• Fluorescent lighting: Fluorescent lighting is used in many indoor spaces in New Zealand and it can create problems, particularly for IP cameras. The frequency of the fluorescent lighting and the power source can clash which creates a constant flicker on the live and recorded video image. Accurate colour information may also be affected. Note that this problem can also affect some standard analog CCTV cameras with CCD image sensors.

• IP camera cable distances are limited to 100 metres between the camera and network switch by structured cabling regulations. It is possible to run Cat5 cabling that will allow analog cameras to be mounted up to two kilometres away from the DVR.

• Virtually any standard Analog CCTV camera will plug in to any DVR allowing you to easily customize and upgrade your system. An IP surveillance system is set up specifically to work with the network protocol it is designed for. This means different IP camera and NVR brands may not be compatible.

• The image from a standard Analog CCTV camera is processed and compressed at the DVR (not the camera) it can be viewed live with no delay. IP cameras can experience ‘lag’ for up to 2-seconds.

• Overall the IP camera is the better model, it offers a clear image, multiple features and enables you to access the video with ease. IP cameras are a worthwhile investment and can prevent petty crimes and even offer detailed footage of any criminal damages.