The focal length can be changed within a certain range to obtain different wide and narrow field angles. Camera lenses with different sizes of images and different scene ranges are called zoom lenses. In the case of a certain object distance of the lens, as the focal length of the lens becomes larger, the screen range of the monitored scene seen on the monitor at the end of the system becomes smaller, but the screen details become clearer and clearer; and as the lens specifications With the increase of, the picture range of the monitored scene seen on the monitor at the end of the system will increase, but the picture details will become more and more blurred.
Which industries can optical zoom cameras be used in
Among them, the zoom camera is divided into electronic zoom and optical zoom. Electronic zoom is actually to continuously expand the image. Since the focal length does not change, the size of the image placed on the CCD does not change, so the definition of the object you shoot becomes blurred as it expands. Digital zoom has no practical meaning. Simply put, it’s like taking a screenshot on a computer and then zooming in on the screenshot. The actual pixels of your picture are still so many, so the more you enlarge the screenshot, the less clear it will be.
Optical zoom is produced by changes in the positions of the lens, object, and focus. When the imaging surface moves in the horizontal direction, the vision and focal length will change, and the farther scene becomes clearer, which makes people feel like the object is progressive. Therefore, there must be two ways to change the angle of view, one is to change the focal length of the lens, by changing the relative position of each lens in the zoom lens to change the focal length of the lens; the other is to change the size of the imaging surface, that is, the size of the imaging surface The diagonal length.
The zoom lens can change the shooting range by changing the focal length without changing the shooting distance, so it is very conducive to picture composition. Since a zoom lens can also serve as several fixed-focus lenses, the biggest feature of a zoom lens is that it realizes the function of changing the focal length of the lens at will. Unlike a fixed focal length lens, a zoom lens does not rely on a quick change of the lens to achieve the focal length change of the lens, but by pushing or rotating the zoom ring of the lens to achieve the focal length change of the lens. Within the zoom range of the lens, the focal length can be steplessly changed. , That is, any focal length within the zoom range can be used to shoot images, which creates conditions for achieving diversified composition.
When using a zoom lens to focus, it is best to consider first adjusting the image to the maximum point for focusing; use the longest focal length end of the lens to focus. Then, reduce the focal length to the focal length expected when shooting. During this process, all the effects on the focal length are always clear. With this technology, since it is focused under the largest possible image, it is easier to observe whether the details of the image are clear, so it is also the most accurate focusing method. Zoom cameras have a wide range of applications and can be used in industries, medical, smart security, drones, robots and other fields.
Post time: Sep-23-2021