Types of Security Cameras
Indoor Cameras:Indoor cameras come in all types, sizes and styles. The most popular is the smoked mini dome camera. The dome camera can be mounted on the ceiling or wall and adjusted to view any angle. Although the dome is designed to protect the camera inside, they are not weather tight and should not be installed where they are exposed to moisture or extreme temperatures.
Outdoor Cameras:
The only difference between indoor and outdoor cameras is that the outdoor cameras are in an environmentally protected housing. Some housings have heaters and blowers to keep the temperature inside within the operating parameters of the camera. Others such as the mini outdoor bullet cameras generate their own heat for operation. All outdoor cameras discussed in this guide are designed to operate in -10 degrees to 120 degree temperature.
Day/Night or Night Vision:
Affordable night vision cameras are the latest innovation to the video surveillance industry. There are many types and styles to choose from but they all have one thing in common, infrared LED's. Small LED's that transmit out infrared light surround the cameras lens. The LED's cast out light the camera can see but the human eye cannot. The distance a camera can see in the dark is based on how many LED's the camera has. As a rule a camera with 10-20 LED's can see 20 feet in complete darkness. Some cameras such as the one below can see up to 70' in complete darkness. Notice the LED's surrounding the camera lens.
Low Light Cameras:
Low light cameras are color cameras which need very little light to operate (.1 lux). They work well in most applications but they do require some lighting, similar to the lighting provided in a romantic restaurant.
Pan Tilt Zoom Cameras:
PTZ cameras, as they are called, are considered "top of the line" in security cameras. They can pan 360 degrees, tilt 270 degrees, and optically zoom in as much as 22 times. They are controlled and programmed with either a desk top joy stick control or through the software of a PC based DVR. They come in both indoor and outdoor versions, can be wall or ceiling mounted, and can be equipped with color Day/Night cameras or night vision.
The cameras can be programmed to automatically run pre-programmed tours, automatically panning, tilting and zooming to predetermined locations. They can also be programmed to pan, tilt and zoom to a specific view if motion is detected or a pre-defined alarm occurs. A user can override the automatic operation and control the cameras as needed. Up to 16 PTZ cameras can be installed on most DVR systems (as long as the DVR supports 16 cameras). The cameras are controlled with a two wire communication wire which loops from one camera to another. Each camera has dip switches which are used to set its address. The comm. wire can have a maximum distance of 3000 feet. In addition to the communication wire each camera also required a video cable to transmit the video signal back to the front end.
On DVR's the communication cable terminates on a PTZ Netcom control board installed in the DVR. This control board interfaces the software and mouse commands with the cameras. On time lapse and other systems the cameras are controlled with a desk top joy stick control. One down side to the joy stick control is it does not provide the ability to control the cameras remotely.
