were based on ideas about propulsion systems like advanced ion thrusters, and magnetically confined fusions like deuterium-3 and helium-3. The models took 150 hours to create. For a scene in which the spaceship passes Jupiter and Io, they filmed different elements in separate film stocks; each shot "required four separate passes of the negative through the camera, each time being rewound to heads and rethreaded to a common start frame". The camera was placed on a motorized dolly. Io was filmed first, then Jupiter, then the spaceship. Some scenes, including one at Saturn, were filmed at a homemade animation stand; others used a discount version of the slit-scan photography kit used for 2001. Models were attached to a modified auxiliary peg bar, near which the glass sheet with the starship was suspended. To film extremely slow scenes, several motors and control devices were tested; zoom motors were determined to work the best. To add movement to the shots, a geared head and a custom gear operated by the zoom motor were used, creating a slight pan. They filmed all these scenes on 16 mm film first to ensure that they could be replicated on IMAX. Bellows and close-up lenses by Hasselblad were used for the penultimate nebulae shots; the camera was facing a water-filled tray. The nebulae were a mixture of black ink and white enamel paint, with color coming from lighting gel. The materials' temperature, thickness, size, and type had to be precise to achieve the reaction. Because the crew had to film these specific shots at 96 fps, mineral oil and paint thinner were poured into the tray the slow down movement; the latter was favored because it created more-interesting movements akin to the three-dimensional effect. Often, a small wire was shaped and dipped into the tray to create specific patterns. Special effects designers Jim Palmer and Barney Kaelin created the laser beam effects; they had |experimented with various types of patterns pre-production. Overall, the space sequence took four-and-a-half months to prepare, test, and film. Post-production To Fly! was edited by MacGillivray and Freeman, with Alexander Hammid supervising, on a Moviola. Knowing they would experiment with editing styles, the film's shots were directed beforehand to allow them to do so. Pacing is normal so audiences have enough time to explore the entirety of the shots. In the opening, the part where Ezekiel is still at ground is windowboxed