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Depending on what you want to achieve with your surveillance, there are five main network camera types to choose between:
Fixed network cameras
Fixed dome network cameras
Covert network cameras
PTZ network cameras
Thermal network cameras
Axis also offers video encoders/decoders, system products and accessories, but in this course, we’ll focus on the network cameras.
A fixed network camera is a camera that has a fixed viewing direction once it is mounted. It may come with a fixed, varifocal or motorized zoom lens, and the lens can easily be changed.
A fixed camera is the traditional camera type where the camera and the direction in which it is pointing are clearly visible. This type of camera is the best choice in applications where it is advantageous to make the camera very noticeable.
Fixed cameras can be installed in protective enclosures. Axis’ outdoor fixed cameras come pre-installed in housings. Fixed cameras can also be mounted on a pan/tilt motor for greater viewing flexibility.
Fixed dome network cameras
A fixed dome network camera is a fixed camera in a dome design. It may come with a fixed, varifocal or motorized zoom lens, and the lens may be exchangeable. The camera can be set to point in any direction. Its main benefit lies in its discreet, unobtrusive design, as well as in the fact that it is difficult to see the direction in which the camera is pointing.
This kind of camera is also resistant to tampering. Axis’ fixed dome cameras provide different types and levels of protection such as vandal- and dust-resistance, and IP66 and NEMA 4X ratings for outdoor installations. The cameras can be mounted on a wall, ceiling or pole. A fixed dome with a wide-angle lens and a megapixel sensor that provides a 360 degrees field of view is often referred to as apanoramic or 360 degrees camera.
Covert network cameras
Covert cameras are designed to blend into the environment and be virtually impossible to discover. They can be placed at eye-level at entrances or integrated into devices such as ATM machines for discreet or covert surveillance.
Covert cameras can enable close-up shots foridentification purposes or overview surveillance. Tampering risks are also reduced. Using a pin-hole lens, Axis’ indoor/outdoor covert network cameras provide resolutions of up to 1 megapixel, including HDTV 720p, and come pre-mounted with an Ethernet cable for both power and data. The cameras are ideal for use in retail stores, banks and hospitals.
PTZ network cameras
A PTZ camera provides pan, tilt and zoom functions(using manual or automatic control), enabling wide-area coverage and great details when zooming in. An Axis PTZ camera usually has the ability to pan 360 degrees, and tilt 180 degrees or 220 degrees, and is often equipped with a zoom lens.
PTZ cameras are available in various form factors; the most common is a PTZ dome, which is ideal for use in discreet installations because of its design and mounting, and because observers have difficulty in seeing the camera’s viewing angle. In outdoor installations, the cameras are usually mounted on poles or the walls of a building.
In operations with live monitoring, PTZ cameras can be used to follow a person or object, and zoom in for closer inspection. In unmanned operations, automatic guard tour on PTZ cameras can be used to monitor different areas of a scene. In guard tour mode, one PTZ network camera can cover the same area where many fixed network cameras would otherwise be needed. The main drawback is that only one location can be monitored at any given time.
Thermal network cameras
Thermal network cameras create images based on heat that radiates from all objects. Images are generally produced in black and white but can be artificially colored to make it easier to distinguish different shades. Thermal images are best when there are great temperature differences in a scene; the hotter an object, the brighter it appears in a thermal image.
Thermal cameras are ideal for detecting people, objects and incidents in shadows, complete darkness or in other challenging conditions such as smoke and dust. Since thermal images do not enable reliable identification, these cameras are used primarily to detect suspicious activities. Therefore, they complement and support conventional network cameras in a surveillance installation.
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