Analog vs. Digital Security Cameras

Analog System Overview

The following diagram depicts the basic setup of an analog camera system. These systems are very popular because of the quality of the components and robust quality of video. Analog is more than sufficient for remote monitoring by Aclarity Systems. Customers may opt for a digital system when very high quality is needed (facial recognition, license plate recognition, or ability to digitally zoom distances of 100+ ft)

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 sends it remotely to Aclarity servers. 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.

Aclarity Systems requires sites to utilize an Everfocus brand DVR. We standardized our system around this company’s technology for a number of reason. For a light commercial or residential customer, Everfocus’s technology offers excellent quality at a very reasonable price. Based on our experience, Everfocus has also proven to be highly reliable.

When choosing an analog system, there are some options. Our installation team can help you determine which type and brand of cameras is appropriate to use.

In general, there are three main types we utilize:

  1. High dynamic range cameras – Use in situations where there is a large range of light in the view (ie. a glass front door). These cameras will maintain image quality in these highly variable situations.
  2. Dome cameras – These cameras are very popular for indoor uses because they are very flexible with the views they record. Also, most people do not know which direction they are pointing, which further deters crime.
  3. Outdoor cameras – Placing cameras in an outdoor cameras requires a metal jacket to protect the camera from the environment and from physical attacks (ex. baseball bat).

Digital Camera System Overview

The latest innovation in surveillance technology is the use of IP cameras.The primary benefit of IP cameras is the high resolution they offer. The resolution can be 2-3 times higher than analog cameras.

In the IP world, each network camera captures an analog image but immediately converts it to digital inside the camera. Some digital processing can happen right at the camera, such as compression and motion detection. The digital video stream is then broadcast over the IP network using Ethernet (CAT5) cable. The power supply may be plugged in at the camera or can be run over the ethernet cable by using Power-Over-Ethernet (POE) adapters. The CAT5 cable for each camera is plugged into a switch which feeds into the network hub. As with all network devices, some set-up needs to be done for each network camera to set up its IP address and other identifying attributes.

Software is required on each PC that you want to view the cameras or playback video. Another high powered PC is set up with the appropriate software to record the cameras. Since communication standards are not consistently followed in this industry yet, the viewing and recording software must be purchased from the same vendor that sells the IP cameras. This can make switching or mixing camera vendors very expensive.

The IP camera signal is broadcast over the Internet in the same way that a DVR signal is. However, each camera is a separate stream and has its own IP address or port. This can greatly affect bandwidth as we’ll see below. When viewing remotely each camera can be pulled up individually by its IP address. If you want to see all of the cameras side-by-side, additional software (again, from the same camera vendor) must be installed.

For most remote monitoring applications, the resolution afforded by IP cameras is not needed. However, even if a lower quality image is transmitted to the Aclarity data room, on the location’s hard drive, the higher resolution video will remain. This can come in handy for criminal identification later on.

IP solution recommendation:

Aclarity Systems recommends using Vivotek digital IP equipment. Like our analog company recommendation, Vivotek offers excellent quality for a reasonable price. While this system will invariably cost a premium to an analog sytem, we believe Vivotek offers a good value for those seeking higher quality video. To view Vivotek’s solutions, please visit their website (vivotek). Of course, our sales team will be able to provide recommendations for the right equipment based on your needs.

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