What is the significance of close-up in portrait photography?

A lens that takes a portrait of the face and a part of the subject. Created by early American film director David Walker Griffith (1875- 1948). A close-up shot is the shot with the closest sight distance in the movie screen. Because of its small viewing range and single picture content, the performance object can stand out from the surrounding environment, resulting in a clear visual image and emphasized effect. Close-ups can show the subtle emotional changes of the characters, reveal the instantaneous movements of the characters, and make the audience strongly infected visually and psychologically. The combination of close-up shots and other scenery shots can create a special montage rhythm effect through the change of lens length, distance and strength.