There are two frequently used terms I would like to clarify.

Diegesis

The narrative world of the film, conceived as a unity. The two main areas in this study where a distinction has been made between the diegetic and the non-diegetic are with the soundtrack and the audience. Music or sounds which are diegetic can be heard by the characters within the film. A soundtrack added to the film afterwards will normally be non-diegetic: Marion does not hear the pounding violins in PSYCHO. But sound effects may also be non-diegetic: the characters in JUNO AND THE PAYCOCK do not hear the machine gun shots which punctuate the breaks between the film's acts. By contrast, sound emanating from any source within the diegesis – whether or not we can see the source, which may be off-screen – is diegetic. Similarly, a diegetic audience refers to an audience within the film, and is referred to in that manner to distinguish it from an audience watching the film.

In fact, Hitchcock also includes visuals which are non-diegetic, albeit rarely. The shots of dancers swirling to ‘The Merry Widow Waltz’ which punctuate the narrative of SHADOW OF a DOUBT from time to time are not, say, flashbacks or what Uncle Charlie is imagining (if that were so, they would be diegetic). They are outside the narrative world, and so are non-diegetic.

Point-of-view editing

Following David Bordwell in Narration in the Fiction Film (Bordwell 1985: 60), when describing shots in a film, I have restricted point of view to mean optical point of view. In other words, what we see on the screen corresponds to the subjective view of someone within the diegesis: the camera is placed where the person is situated and angled to show what he/she sees. Occasionally Hitchcock will cut in closer along the axis of the look to emphasise something (REAR WINDOW includes shots like this), but this is relatively rare: he usually respects the necessary distance. Point-of-view editing is an elaboration of point-of-view shots into a specific sort of sequence. A point-of-view shot of what a character sees (alternatively called a subjective shot) is followed by a reaction shot – usually in medium shot or close-up – of the person looking, which is followed by another point-of-view shot and then another reaction shot and so on.