IP CCTV Camera
The IP camera is a type of CCTV camera image and transmits it through an Ethernet network (local area network, intranet or internet ).
It allows viewing the monitored area from a web browser, or when a specific application on a computer, network, or remotely. The images provided are therefore accessible from anywhere and by several people simultaneously.
This type of CCTV camera defined on Securitypology.com,this little a few years ago made its way gradually into the professional video surveillance equipment market. Dependent on network performance, it was difficult for them to break it in a few years.
Today however the very high internet speeds are common, and the IP camera knows enjoy. Indeed, their technology evolved and they now equal analog cameras ( analog cameras Guide ) while providing more opportunities, more control especially easy remote access!
A digital signal
Because they transmit their information via the network to which they are connected, IP cameras use a digital signal carried by a RJ45 cable.
A digital signal is a varying signal discontinuously in time. Therefore, it is easily copyable and memorable. Registration of IP CCTV cameras images is very easy.It is not only the advantages brought by the use of a digital signal:
- Noise Immunity: A digitized signal is immune to interference
- Flexibility: It is easy to work and adjust a digital signal.
Connectors and cables
As we have seen, the IP CCTV cameras are connected to the network through an RJ45 cable.
This multiple roles: It allows course of the video signal , but it also makes it possible to supply electricity and in some cases, to control the movements of the camera.
To see: The Cable Guide.
For this type of camera, the RJ45 cable only to send the video stream.
You need a separate power cable to power the camera.
It is fixed, so no motion control.
IP / POE Camera
OCB technology to switch the power supply in the RJ45 cable.
Thus, the video and power pass through the same cable.
It is also fixed, so no motion control.
IP PTZ Dome Camera
These cameras are mobile, they can turn on their own and orient differently the camera.
The movement commands can be transmitted via the RJ45 cable, but other alternatives are possible, including through RS232 or RS485.
In this case, the cable RJ45 can carry the video signal.
Power is supplied by a separate cable, the necessary power being high due to the motor for rotation.
If you wish to purchase a video surveillance system with IP cameras, there are certain criteria to consider and verify before purchasing the equipment.
The visual field
Expressed in degrees of angle, it means the area that objective is able to film or photograph.
The focal length determines the width of the field captured by the CCTV camera. A wide angle lens with a shorter focal length than a telephoto lens, but its visual field is broader.
The opening and exposure
We associate the opening of a goal to the letter f.
This figure f sets the aperture and therefore the amount of light that can pass through the lens. The lower it is, the more the ability to collect light is great.
A large opening allows to receive good picture quality even if the monitored zone is unenlightened.
See: goals Guide
Expressed in Lux (brightness scale, with 0 being the most total black), it shows whether a camera is able or not to shoot in the dark.
The higher the value, the higher the sensitivity, meaning it can detect movement in a very strong dark.
The infrared LEDs surrounding the some camera lenses enable a clear image even at night.
When the monitored zone starts to be in the dark, the camera automatically switches to Night-mode and lights the infrared LED.
The infrared faiseau is outside the spectrum of visible light by the human eye. Thereby the illumination of the camera is completely invisible to humans.
Some CCTV cameras can illuminate up to 30 meters and there are infrared headlamps increasing this distance to 100 meters.