Dome Cameras

The dome camera has become the most versatile and popular type of camera used in modern CCTV installations. It is more adaptable than traditional static cameras and the plethora of housings, finishes, coatings, casings and uses is astounding. They can be mounted in a semi-covert manner and blend well into industrial, commercial, retail, leisure or other user environments.

There are basically two types of Dome camera, fixed or fully functional - commonly referred to as 'speed domes'.

Fixed Domes

A static dome camera does exactly what it says - it monitors an area from a single static fixed point. Most modern fixed domes include a 'gimble' and have three-axis flexibility, which allows domes to be mounted on a variety of surfaces and at almost any angle.

There are many choices of internal housings for fixed domes or mini domes with a model to suit most applications, performance criteria and budget.

The internal static mini-dome is the most recognisable, these vary in diameter from 80mm to 120mm dependent on the size and specification of camera it houses; again they come in a selection of colours - black and white being the most common. In recent years the greatest change has been the growth in use and the variants available of vandal proof or vandal resistant static domes, although in essence no unit is truly 100% vandal proof.

Nearly all domes contain a PCB Camera, available in monochrome, colour or colour/mono with or without IR sensitivity. Lenses can be either fixed or varifocal in many different focal lengths and F stops.

Fully Functional Domes

Fully functional dome cameras are also sited at fixed points but unlike static domes they are motorised and controllable, either manually or automatically, to monitor large areas.

These cameras are capable of 360 degree high-speed pan and tilt rotation, panning horizontally and tilting vertically and equipped with integral zoom lenses with automatic focus. The latest versions incorporate intelligent functions such as auto image stabiliser, scene change detection, and auto tracking, delivering outstanding reliability for outdoor surveillance applications.

A fully functional dome consists of two basic parts, the 'head' and the 'housing'.

The 'housing' is the most visible part and is the casing or jacket into which the head is located.

It has a clear or coated polycarbonate cover and contains the electrical connections and wiring looms for power, video, data, alarms, heaters etc.

The 'head' is the workhorse component of a fully functional dome; containing the camera module, usually colour or colour mono, and the motors and control logic necessary for the domes' specification.

Camera modules can have a variety of features, including an integral lens with an optical range up to 30 x zoom.

As with static versions, fully functional domes can include additional features to enhance image quality in varying light conditions, proportional zoom, allowing the camera to remain focused during movement.

Using a keyboard controller, the communication protocols enable the dome to be remotely controlled and also programmed to automatically undertake a series of pre-determined positions called presets. The operator is also able to program a tour, which is a series of timed presets, or pattern tour where the keyboard is used to guide the camera through a sequence of movements using the joystick.

Although keyboard controllers are the most common method of dome control they can also be controlled via a matrix or PC. The keyboard joystick is used to control the dome by moving it to the left/right for pan, up/down for tilt and a twist for zoom.

The head may include alarm monitoring which are usually assigned to a preset position so that if the device is triggered the dome travels immediately to that position.