Realism in Cinema

The central tenets of Bazin's theory of realism in cinema can perhaps best be summed up as the use all elements in a scene to create an emotional response in the audience. He was, in a sense, the antithesis of of the Soviet montage editors of the same time period. Soviet editors such as Eisenstein took the approach that each shot of a scene should be used as a piece of a puzzle, incomplete by itself, but contributing to the overall impression when viewed as a sequence.
Bazin, on the other hand, believed that excessive editing in a film gave an overly simplistic, one dimensional view of reality. In place of the fragmentary approach used by the formalists of the montage school, Bazin used methods that stressed the complex and continual interactions of all elements in a scene.
. In short, the approached used by the"realist" school tended to encourage more audience interpretation of the action in a film, whereas the montage school used editing to convey the director's impression of the action to the audience.
As a comparison between the two styles, contrast the the use of multiple scenes in the film "Potemkin" with the lengthy takes ( and very few scenes) of the film "Clerks". In the first film, many shots of short duration combine to give an overwhelming sense of confusion and chaos, even terror; in the second, fewer shots and extensive dialogue, are used to produce a sense of ordinariness that most people can relate to on some level.
An excellent synthesis of these two editing styles can be seen in the film "Raging Bull", where the scenes involving Jake LaMotta's personal life are shot in a realist, semi-documentary style, and the boxing scenes use numerous shots, camera angles and slow motion photography to show the chaotic action inside the boxing ring.The movie, shot in black and white, opens in 1964, with LaMotta working as a nightclub comedian, then flashes back to the start of his boxing career in 1941. LaMotta's private life, from his love - hate relationship with his brother, to his jealous obsession with his wife Vicki, to his fall from grace and coming to terms with his life is chronicled in a series of long, dialogue heavy scenes ; the viewer is able to follow the interaction of the characters in a way that allows him to relate to them. The scenes inside the ring , in contrast, are much shorter; close ups, medium shots and different angles bombard the viewer, conveying the speed and unpredictability of the action. This same  technique is at the heart of the "montage" school of editing. In this film, both techniques are used in conjunction, to give a sense of dramatic irony to the movie, as the audience becomes aware of what LaMotta does not, namely, that the intensity that makes him so formidable inside the ring is the source of most of his problems outside of it.
  I would gives this film a thumbs up for its artful blending of the realist and montage schools of directing, not to mention, it's a very watchable movie.