What were the main special effects used in the movies of the 20s and 60s?

According to the Internet

Chinese movie special effects were in the budding stage in the 1950s and in the stage of independent research and development in the 1960s

Budding in the 50s

In 1950, according to the directives of the Central Administration of Motion Pictures, special effects departments were set up in the Northeastern China, Beijing, and Shanghai studios, and the Northeastern China was responsible for professional training and internships for the special effects personnel chosen by the studios. In 1953, Shanghai Film Studio officially set up a special effects department with a full range of jobs. 1955 The Match of the Immortals was the first film to develop and apply the special effects process of "color separation". 1956 Battle in the Desert was the first film to apply the composite photography process of frame-by-frame projection of spatial images, and the black-and-white film began to have more and more new features. Black-and-white movies began to have more and more novel images.

The 1960s saw the rapid development of special effects in Chinese cinema

The 1960s saw the rapid development of special effects in Chinese cinema, with each studio developing its own technology. 1960 saw the development of split-shade special effects photography for the filming of The Lotus Lantern, which was later perfected for The Monkey King.

Rebirth in the 1970s