lens
The lens of a camera is an optical system formed by the combination of several lenses and mirrors that offer a real image on the sensitive surface of the camera. In other words, it is the objective that will determine the angle of view of the spy camera. The first feature to be taken into account for this is the focal length which represents the distance between the optical counter of the lens and the sensor. There are several sizes ranging from 2.8mm to 100mm so you can choose based on the vision you want. The larger the focal digit of a lens, the narrower the angle of that lens. This makes you feel that the subject is closer. Conversely, when the focal length figure is small, the viewing angle widens, giving the impression that the subject is further away. Devices such as the spy camera light bulb or theCamera clock are equipped with lenses ranging from 2.8 to 3.6 mm to give you a wider angle of view.
A lens can have a fixed focal length, that is, a focal digit size and that's it. Other devices are equipped with multiple focal lengths. This is called zooms. In this case, the shortest and longest focal length is shown on the device.
