What does mf mean?

MF (Manual Focus) refers to manual focus.

Manually adjust the focus ring to make the subject clear and the background change the depth of field as needed. It takes time to adjust, and the efficiency is slow, but the effect is generally the best.

AF (automatic focusing) is automatic focusing, which is simple to operate and divided into three modes. When there is a problem with autofocus, you can use manual focus to adjust it.

Professional name of the camera

AF-S is a single focus, focusing once by half pressing the shutter, suitable for shooting still life, studio portraits, etc. AF-C Canon camera refers to servo autofocus, and Nikon camera refers to continuous focusing. Half-pressing the shutter will keep the focus on the moving subject, which is suitable for shooting moving subjects.

AF-A is autofocus, and the camera decides how to focus: single focus is used for still life and continuous focus is used for moving objects. Select the focus mode according to the action of the subject, and manually adjust the focus when the autofocus is wrong.

HDR is a commonly used technology in photography, which is the abbreviation of English High-DynamicRange, meaning "high dynamic range". HDR technology can overcome the shortcomings of limited dynamic range of most camera sensors, and control the tone of the picture within the range that can be recognized by human beings. It can superimpose multiple photos with different exposures into a delicate image.