Camera housings and outdoor installations

Outdoor casing suitable for use with Axis network cameras.

Camera housings

If a camera is to be mounted outdoors or in relatively hostile environments, it needs a weatherproof or vandal-proof housing to protect it. Camera housings come in different sizes and qualities and some versions have built-in fans for cooling and/or heaters.
See list of protective housings from Axis.

Lenses

An auto iris lens should always be used for outdoor applications. An auto iris lens automatically adjusts the amount of light that reaches the image sensor. This optimizes the image quality and
protects the image sensor from being damaged by strong sunlight.

Reflections

If the camera is mounted behind a glass, such as in a housing, the lens must be placed close to the glass. Otherwise, reflections from the camera and the background will appear in the image. To reduce reflection, special coatings can be applied on any glass used in front of the lens.

Lighting

When using cameras at night, additional external lighting may be required. This should be arranged to avoid any reflections and/or shadows. For covert security, infrared (IR) illuminators can be used instead of normal lighting, known as "white light". IR light is imperceptible, which means that while it is sufficient for capturing images from IR cameras, it is not visible to the human eye.

IR lamp suitable for use with Axis day & night, as well as IR-sensitive network cameras.

It is possible to connect IR-sensitive network cameras directly to the network, or to connect traditional IR-sensitive cameras to a network via a video server. Note: Color cameras do not work with IR light. Some cameras are able to automatically switch between a daylight color mode and an IR mode useful in night vision where the image will then appear without colors. See also Day & night functionality.

Avoid direct sunlight

Direct sunlight should always be avoided in an image. Direct sunlight will "blind" the camera and can permanently bleach the small color filters on the sensor chip. If possible, the camera should be positioned facing the same direction as the sun.

An image from a camera where the image sensor filters have been destroyed by the sun.

Contrast

Viewing too much of the sky results in too much contrast. The camera will adjust in order to achieve a proper light level for the sky. Consequently, the object/landscape of interest will appear too dark. One way to solve this problem is to mount the camera high above the ground; using a pole if needed. Sturdy mounting equipment should always be used to avoid vibrations caused by strong wind.