Filming
Principal photography took place in Tassili N'Ajjer, the Illizi Province of Algeria (to depict Chad), Brunswick Centre, London, St. Georg (Bogenhausen), Munich, Las Ramblas, Barcelona and locations across south-eastern Spain (Almería, Madrid, Seville, Malaga Sorbas) throughout mid-to-late 1973.
In a long take, early in the film, Nicholson's character Locke is switching photos, between Locke's and Robertson's passports, in his hotel room, with a tape recording playing an earlier conversation between Locke and Robertson, now dead. The camera pans for 25 seconds, without a cut, to hold on Robertson's now live appearance on the balcony, when Locke appears beside him and the two of them continue talking (i.e. an in-camera in-single-shot flashback).
The execution of a prisoner in this film is not staged. It consists of actual footage of a real execution that the crew filmed while on location.
The film's penultimate shot is a six-minute, 32-second long take tracking shot which begins in Locke's hotel room, looking out onto a dusty square, pushes out through the bars of the hotel window into the square, rotates 180 degrees, and finally tracks back to a close exterior view of the room's interior.
The location of the hotel is stated to be Osuna in the film. However, the bullring at the edge of the square is recognizably that of the one in the Spanish town of Vera, in the province of Almería. In a DVD commentary, decades later, Nicholson said Antonioni built the entire hotel so as to get this shot.
The shot was continuous, preventing adjustment of the lens aperture as the camera left the room and entered the square. Therefore, the footage had to be captured in the late afternoon near dusk to minimize lighting contrast between the brightness outside and inside the room.
The camera ran on a ceiling track in the hotel room and when it came outside the window, was meant to be picked up by a hook suspended from a giant crane nearly 30 meters high. A system of gyroscopes was fitted on the camera to steady it during the switch from this smooth indoor track to the crane outside. Meanwhile, the bars on the window had been given hinges. When the camera reached the window and the bars were no longer in the field of view, they were swung away to either side. At this time, the camera's forward movement had to stop for a few seconds as the crane's hook grabbed it and took over from the track. To hide this, the lens was slowly and smoothly zoomed until the crane could pull the camera forward. Then the cameraman walked the camera in a circle around the square, giving the crew time to shut the window bars before the camera returned to look through the window from the outside this time. Antonioni directed the scene from a van by means of monitors and microphones, talking to assistants who communicated his instructions to the actors and operators.
Although this is often referred to as the "final shot" of the film, it is not; the last passage shows a small driving school car pulling away in the twilight, and the camera holds on the hotel as the film's credits begin to roll.
