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Types of HD CCTV


There are several differnet types of HD CCTV on the market and they are all subtly different. It's important to make sure you choose the right type.

HD-SDI

This was was the first analogue HD technology widely available and was supposed to allow HD over existing coax cable. There were 2 main problems, you needed really good quality coax cable which meant systems had to be re-wired anyway and the maximum cable runs were quite short. You needed to fit boosters or repeaters every so many metres. The other problem with HD-SDI is you can't use CAT5 cable. Most people want to use CAT5 because it's future proof and easy to run. Finally HD-SDI is not backwards compatible with standard definition CCTV.

 

HD-CVI

This technology is manufacured by a single company in China - Dahua. Even within the CVI family there are compatability issues, 720P wasn't compatible with 1080P and there are a couple of different generations with later equipment not being fully compatible with previous equipment.

 

HD-TVI

This is our preferred technology. It is fully compatible with standard definition analogue cameras (D1 and 960H resolution), 720P and 1080P are both supported although we only sell the higher resolution 1080P cameras. Cable runs can be made in CAT5e or CAT6 cable using video baluns just as you would with standard CCTV. As with standard definition CCTV HD-TVI allows long cable runs without the need for repeaters. The other great thing about TVI is that unlike HD-CVI which is only available from one comapany HD-TVI was developed by the American company Techpoint and is supplied as an open platform this means it is used by many different manufacturers.

 

HD-AHD

Another technology from China. The big benefit is cost, it's cheap. Image quality isn't as good as HD-TVI and it is more limited in terms of hybrid compatability.

 

IP

IP technology is well proven and theoretically allows very high resolutions to be achieved. There are some potential problems with IP CCTV though which means we don't favour it. A high definition IP CCTV system puts a lot pressure on the network. In many cases the camera resolution has to be choked down so as not to cause an overload. If there are any network problems the whole CCTV system fails.

IP CCTV systems tend to be quite complicated involving switches, an NVR, some form of power injection, potentially a seperate network storage device and in a lot of cases licences have to be aquired to fully utilise the equipment. The cameras themselves can be expensive particularly when dealing with longer range external cameras.

Some people think that IP is the only option if you want to remote access a CCTV system. This is absolutely not the case. All our HD-TVI DVR recorders can be remote accessed.

 

Please feel free to call and discuss the various HD options available on the market.