What are focusing, focusing and zooming?

1, focusing: refers to adjusting the focal length when using the camera. The English name is Focus, which is an action that you can adjust the focus ring on the camera to display the subject clearly. Generally, digital cameras have various focusing modes, namely, auto focus, manual focus and multiple focus modes.

2. Focusing: the process of controlling a beam of light or particle flow to converge to one point as much as possible. For example, a convex lens can focus parallel light on the focus of the lens; In the electron microscope, the electron flow can be focused by using magnetic and electric fields. Concave mirror is used for radar to focus VHF. Focusing is a necessary condition for imaging.

3. Zoom: Another key point of the lens is zoom ability. The zoom capability includes optical zoom, digital zoom and hybrid zoom.

Although it is helpful to enlarge distant objects when shooting at a long distance, only optical zoom can support adding more pixels after the main body of the image is imaged, making the main body not only larger but also relatively clearer.

Usually, the larger the zoom factor, the more suitable for telephoto shooting. Optical zoom, like traditional camera design, depends on the focal length of the lens, so the resolution and image quality will not change. Digital zoom can only reduce the size of the original image and make the image larger on the LCD screen, but it does not help to clarify the details.

Extended data:

Zoom lens is a kind of camera lens that can change the focal length in a certain range, so as to get different field of view, different images and different scene ranges.

Zoom lens can change the shooting range by changing the focal length without changing the shooting distance, so it is very beneficial to picture composition.

Because a zoom lens can also serve as several fixed-focus lenses, it not only reduces the number of photographic equipment to carry when traveling, but also saves the time for changing lenses.