How to focus the high-quality camera lenses?

The focusing methods of high-quality camera lenseses mainly include automatic focusing and manual focusing. ‌
Auto focus (AF)
Half press shutter: Set the camera to autofocus mode (AF mode). When the shutter is half pressed, the camera will automatically activate the autofocus function, and the lens will rotate the focus ring until a "beep beep" indicates successful focusing. ‌
Touch screen selection of focus point: In autofocus mode, the focus point can be selected through the touch screen, and the position and size of the focus frame can be adjusted to meet different shooting needs. ‌
Manual Focus (MF)
Rotating focus ring: In manual mode, the photographer needs to rotate the focus ring on the lens to adjust the focal length. Observe the clarity of the image in the viewfinder or display screen until it reaches the desired state.
Maximum aperture setting: When manually focusing, it is recommended to first set the aperture to the maximum aperture of the lens (such as f/1.8) for easier focus recognition. ‌
Lock focus: After focusing is completed, the focus should be locked to ensure the accuracy of the focal length and avoid misoperation between manual and automatic focusing.
Basic steps and techniques for focusing
Observing the viewfinder or display screen: Whether it is automatic or manual focusing, it is necessary to carefully observe the changes in image clarity in the viewfinder or display screen until the desired state is achieved.
Familiarize oneself with the subject and distance: Beginners can start practicing from the maximum aperture and gradually become familiar with the feeling of adjusting the subject and distance.
Maintain camera stability: During the focusing process, it is important to keep the camera stable and avoid shaking that can affect the imaging quality.
Focus differences of different types of lenses
Fixed focus lens: such as 50mm f/1.8, with a fixed focal length, focusing is mainly achieved by manually rotating the focus ring to adjust the image clarity.
Zoom lens: such as 24-70mm f/2.8, its focal length can be adjusted within a certain range, and the zoom effect can be achieved by rotating the zoom ring.