A zoom lens is a type of camera lens that allows the user to change the focal length, or zoom in and out, while still maintaining a constant level of image quality. A zoom lens is typically made up of a series of individual lens elements, each of which is responsible for a different aspect of the overall image.
The most important element in a zoom lens is the zoom group, which is made up of the lens elements that actually do the zooming. The zoom group is usually located towards the front of the lens, and is made up of a series of individual lens elements that can be moved independently of each other. In order to zoom in or out, the user simply adjusts the position of the zoom group relative to the rest of the lens.
Another important element in a zoom lens is the focus group, which is responsible for keeping the image in focus as the focal length is changed. The focus group is usually located towards the back of the lens, and is made up of a series of lens elements that work together to keep the image in focus.
The final important element in a zoom lens is the aperture group, which is responsible for controlling the amount of light that passes through the lens. The aperture group is typically located towards the front of the lens, and is made up of a series of blades that open and close to control the amount of light that passes through.
