35mm. Even in his films before his prodigious decade (60s), in which he acquired an authorism's style (the metaphysical drift, above all), one can see what a great filmmaker Bergman is, above all at the level of image composition. Look at the whole long initial sequence in the photographic studio, without dialogue and the scene in the rain at the train window: how photogenic are the subjects under his look!
Bergman does a Woman’s Film. Many Bergman films are full of or centering on women but its interesting how one of his least critically successful films is one of the few where the women don’t begin and end the film neurotic and suffering. To deride this as a “stylized melodrama” is to forget that that’s what the majority of Bergman’s films are.