Photography and videography are common tools in implementing security. These measures can monitor and capture images of suspicious or criminal activity which could then be used to detain wise guys. They need light to work, and leaving the lights on or illuminating all areas are not options for reasons of cost-efficiency and practicality. Night vision cameras are used instead.
These devices are best known for their applications in secure environments. This is only natural, since night vision cameras work best when held still,eg when they are mounted on braces or some other mechanisms. They can capture pictures even if the lights are out, so places of business or banks can turn off the lights and close up shop without caring about loss of security capacities.
Many night vision cameras produce monochromatic images, that is, pictures with only shades of one color. Prime examples are black-and-white pictures and green photographs. This is the result of the technologies they use to capture pictures in darkness. They work well for security cameras and similar devices since color is not a giant issue while lucidity and resolution of the image is. Monochrome is the result of maximizing picture qualities outside of color factors.
One technology used in night vision cameras is image intensification. The camera takes in the view, and particles of energy strike sensitive layers in the camera. These signals are interpreted into something that humans can see, so the use of monochrome where the brighter the color, the more photons or particles there were entering the camera from this point in the area of observation. Normally, photons within the spectrum of visible light are used to operate these cameras, but other categories of radiation from wavelengths outside the visible range for humans are used. Infrared is the most popular. Illuminating an area with high-infrared bathes it in “invisible” light, which makes the scene clear and bright for the properly-equipped camera. This illumination may also be seen with night vision devices, and can serve as deterrents to any thieves who know of the security measures.
The other technology used in night vision cameras is thermal imaging. This is good for applications where you just need to identify something by its silhouette and not by features like faces. Since they need no light and instead sense differences in temperature expressed in low-infrared, they are ideal for placement on perimeters. These are generally wired to alarm systems, which would trip when any “intruder” as defined by the programming would enter the field of view.
