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A surveillance camera should have functions such as rotation, zoom, magnification change, auto focus, etc. to expand the surveillance range. To achieve these functions, the digital video recorder needs to precisely control the camera through a controller.

1. Rotation control

Engineers usually use a pan head to mount and position surveillance cameras. There are two types of pan tilt: fixed head and motorized head. Fixed head is suitable for a relatively small surveillance range. After mounting the camera on the fixed head, adjust the horizontal and elevation angles of the camera to get the best working condition, and then fix the adjustment mechanism to fix it. Motorized heads are equipped with stepping motors, and these motors control the rotation of the camera through signals from the controller to achieve precise positioning, which is suitable for a wide surveillance range.

Based on the way they rotate, the heads can be divided into horizontal pan-tilt and omnidirectional pan-tilt. Usually, horizontal heads can rotate from 0° to 350°, while omnidirectional pan-tilt can not only rotate left and right, but also up and down. Generally, the horizontal rotation speed is 3° to 10°/s, and the vertical rotation speed is about 4°/s. In some high-speed camera systems, the horizontal rotation speed can reach more than 480°/s and the vertical rotation speed can reach more than 120°/s.

2. Automatic zoom, magnification change, and auto focus

(1) Integrated camera: Integrated cameras integrate the lens, CCD chip, video processing circuit, power supply, and housing to achieve functions such as automatic zoom, magnification change, and automatic focus. High-quality products can achieve accurate focus with one operation, while low-quality products may require multiple adjustments to achieve accurate focus. Current integrated cameras usually have zoom functions such as 16x, 18x, 20x, 22x, 27x, and 32x, which increases the optical zoom ratio and is suitable for low-light situations. The zoom ratio mentioned here refers to the optical zoom ratio.

The main technical elements of an integrated surveillance camera include lenses, CCD chips, and DSP processing modules. High-quality lenses are mainly produced by Japanese manufacturers such as Canon, Camputar, and Avenir. CCD chips are mainly produced by Sony and are divided into two types: SuperHAD and Exview, Exview is the latest technology, usually adopts a 1/4-inch size, and has a higher signal-to-noise ratio than SuperHAD. As for the DSP processing chip, Sony's DSP chip has excellent image processing ability, making the image look very vivid. Meanwhile, Canon and Nikon's DSPs perform better in terms of exposure modes and focus.

(2) Use of electric zoom lens + normal camera: Use an electric zoom lens in combination with a normal camera, utilizing the camera's video drive principle to automatically control the focal length, aperture, and focus of the lens. Some manufacturers have developed high-magnification electric zoom lenses such as "60x electric zoom lens D60×12.5", which can reach 750mm (1500mm when using a zoom extender), allowing you to clearly recognize targets 3 kilometers away. WEILAILIFEI's wireless security camera set's optical wide-angle lens with multi-layer lens provides a wide viewing angle of about 130° or more, reducing dead ends in the monitoring area.

Controlling functions such as camera rotation, zoom, magnification and auto focus in low light conditions are essential to extend the surveillance range. WEILAILIFEI provides high-quality surveillance solutions with these functions both outdoors and indoors, ensuring that your various surveillance needs are met.