The task of choosing the right surveillance system is made difficult by a variety of factors. Buyers have to navigate the complex web of CCTV brands, designs, and styles, and then select the cameras with the right combination of specs to fulfill their individual requirements. The average home or business client lacks the technical skills that would enable him/her to choose the right cameras. For this reason, they require assistance from professional security camera installers.
Understanding CCTV Camera Lenses
Camera lenses play a crucial role in determining the suitability of security cameras for particular applications. Below are some of the common terms that are used with reference to lenses.
Focal length refers to the distance between the lens' center and its focus. This is usually denoted in millimeters (mm). The focal length is important in determining the level of magnification that a security camera can achieve. Therefore, users must determine the maximum distance that they would like their surveillance system to cover, to ensure that the camera lens they select is capable of seeing that far. The focal length has a direct effect on the camera's Field of View. Choosing a lens with a bigger focal point increases the distance that a camera can cover, but reduces the Field of View.
Field of View (FOV)
This refers to the width of the area under surveillance that a camera is able to cover. The focal length of a lens influences how wide the picture would be, with smaller focal lengths achieving wide-angle views.
Monofocal vs. Varifocal Lenses
Monofocal lenses have a fixed focal length and thus, can only focus on an object at that specific length. Varifocal lenses on the other hand, can be adjusted manually to different focal lengths to allow viewing of objects at various distances.
Zoom lenses are very similar to varifocal lenses in that, the focal length can be adjusted to improve the definition of an object in focus. However, zoom lenses have an electronic mechanism that automatically adjusts the lens focus.
If you need help understanding the CCTV lenses to buy, talk to the leading security camera installers, I-Tech Security!