TYPES OF LENSES FOR CCTV
The lens is the most important component of a surveillance camera. Our company with specialists will help you choose lens which will be 100% suitable for your specific task.
Varifocal, monofocal and transfocal lens: what is the difference
Performed camera functions directly depend on the lens. Varifocal, monofocal or transfocal lens will determine what opportunities will have a camera. Lens is the eyes of the camera, hence the importance of this element. The lens is based on the principle of an eye: lens gathers the flow of light rays and directs firstly at the focal point, and then to the matrix.
The light is converted into electrical signals by matrix, which are subsequently formed image. Focus, by the way, is the main characteristics of the camera, because the review is determined by the focal length. There are three main types:
- monofocal lens;
- varifocal lens;
- transfocal lens.
Monofocal lens: what is its feature
Monofocal lenses have a constant, fixed focal length. The aperture of the lens unchanged. This solution is ideal for observing the object with a stable lighting. Selection is based on the focal length, connection type and the camera aperture. If the focal distance is higher, obscured edges on the image will be less. It is important to remember that this indicator is unchanged, so choose carefully your device or use the advice of a professional.
As for mounting, here one should look at the camera. Monofocal lens can have a fastening «C» or «CS». The aperture determines in what position the diaphragm is. In any case, monofocal lenses are the great budget solution that is particularly relevant to control in terms of a fixed range.
Varifocal and transfocal lens. What are their advantages
Varifocal lens provides the ability to adjust the focus. This allows user to determine the viewing angle. This feature is extremely useful in practice because if necessary you can always readjust the camera. But setting such a camera is a delicate matter and, therefore, requires the intervention of professionals.
But some models have a zoom. Due to this, the lens offers ability to customize focal length remotely. Transfocal lens is used to monitor open space; it is used with PTZ cameras.