Security Cameras DVR & Surveillance Equipment Atlanta Georgia
Choosing between IP and analog security cameras is one of the first and hardest choices facing any prospective buyer of a CCTV system, whether it is for home surveillance or for monitoring a business. Both types of systems have advantages and disadvantages, and manufacturers don't try to make it easy to decide between them. There is a lot of hype and marketing buzz right now because of the growth of the industry.
Both types of cameras work through the use of CCD and CMOS chips. These chips turn visible light (and in some cases infrared light) into a signal. Analog cameras turn this signal into something that a television can see, very much like a camcorder. IP based cameras do something a little more complicated. They take the information from the chip and feed the analog signal into an encoder. This encoder is combined with an onboard web server. This allows for the camera to become a network device. This allows it to be viewed by users over an existing or new network like a web page.
Analog cameras have been around since the 1970's, starting out as vacuum tube based devices. Since then the cameras have gotten better and better. Improvements to resolutions have occurred every year. But the improvements go beyond increasing resolution. Auto-iris lens have made dealing with florescent lighting situations easier. Backlight controls have been introduced to help with bright lights coming into an area, like light streaming in through a window next to a door. Privacy masks built into PTZs can handle some of the concerns over misuse of CCTV cameras.
Analog cameras have a variety of ways of transmitting the signal, from wireless to coax, to Cat5 using different connector types. This makes long distance runs in the same building much easier since you can use the right and most cost effective cable for each run. The variety of cable types can be both confusing and useful at the same time. Cat5 works for very short runs that are less than 250 ft. Professional grade baluns can be run up to 2500 ft.
IP cameras grew from the humble web cameras. The idea behind them was to move some of intelligence from the DVR to the camera itself. Many of the current IP cameras have their own built in motion detection. This allows some cameras to record to SD cards inside the camera itself, offering a layer of redundancy. Other features include adding an analog output to the camera so that it can become a bridge between an analog system and an IP based system.
IP cameras can be connected to a network by either wireless transmissions or by Cat5. Through the use of switches/hubs/and routers the Cat5 can be extended almost indefinitely. The use of IP cameras can require the installation of new RJ-45 jacks. Existing jacks generally are not well placed to secure the camera's connections. Some IP cameras are hybrid in nature, allowing for both network and analog connections. Toshiba's line of IP cameras generally has this feature.
- Cost: Analog cameras generally have a better price to performance ratio then IP.
- Flexibility of design: There are many varies of camera types, from small covert cameras to large PTZs to indoor domes with IR. This can make fulfilling certain goals easier by using a camera designed for your needs.
- Compatibility: Analog cameras put out either NTSC or PAL signals. In North America, almost any camera you buy will be NTSC. This makes it easy to use existing cameras, or mix and match vendors for equipment.
- Maturity: Many of the teething problems have been worked out. Things like privacy masks (blacking out an area for privacy on a PTZ) and back light compensation exist from lesions learned in the past.
- Analog cameras don't have some of the features like built in digital zoom that IP have, except at the highest price points.
- Wireless Analog cameras have problems with interference and are unencrypted. Anyone can view the signal.
- Analog cameras can be harder to deal with over long distances.
- Better wireless support: Analog wireless has more problems with interference then network based cameras. The 802.11x standards have encryption built into them.
- IP cameras can take advantage of already existing wiring.
- Adding one or two cameras at a remote site can be easier.
- High bandwidth use: It varies by camera but 500kbps to 1.5 Mbps is a common range.
- Cost: Because of the cost of the hardware that is moved onto the camera, IP cameras cost more then comparable analog cameras.
- Vendor lock-in: Many third part applications support more then one type of camera but most vendors only support their cameras. Given that not all brands support all features, it can make selecting the right brand hard unless you turn to a third party.
It is important to assess your situation and evaluate both options, not only for your current needs, but for expansion possibilities in the future as well.