What is focus, focus, zoom?

1. Focus: refers to adjusting the focus distance when using a camera. The English scientific name is Focus. It is an action that you adjust through the focus ring on the camera to achieve the purpose of clearly displaying the subject. Usually digital cameras have multiple focus methods, namely autofocus, manual focus and multi-focus.

2. Focusing: The process of controlling a beam of light or particle flow to converge on one point as much as possible. For example, a convex lens can focus parallel light rays at the focus of the lens; magnetic fields and electric fields can be used in electron microscopes to focus the electron flow; radar uses concave mirrors to focus very high frequencies. Focusing is a necessary condition for imaging.

3. Zoom: Another focus of the lens is its zoom capability. The so-called zoom capabilities include optical zoom, digital zoom and hybrid zoom.

Although they all help to magnify distant objects during telephoto shooting, only optical zoom can support the addition of more pixels after the subject is imaged, making the subject not only larger but also relatively clearer.

Generally, the one with a larger zoom factor is 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 original image size, making the image larger on the LCD screen, but it will not help make the details clearer.

Extended information:

A zoom lens is a camera lens that can change the focal length within a certain range to obtain different wide and narrow angles of view, different sizes of images and different scene ranges.

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 one zoom lens can serve as several fixed-focus lenses, it not only reduces the amount of photographic equipment carried when traveling, but also saves the time of changing lenses.