In draft scripts for the film that would become "Star Wars", the term "Stardestroyer" refers to two-man fighters flown by what would become the Galactic Empire. The film's second draft features four Star Destroyers chasing a single Rebel ship, but the tremendous costs incurred by Industrial Light & Magic (ILM) when production began helped lead Lucas to use a single "terrifyingly large" Star Destroyer instead of four. ILM built a shooting model that was about half the size of the model for the "Tantive IV" the Star Destroyer was chasing. Lucas asked ILM to build a larger Star Destroyer model to match the "Tantive IV"'s scale, but ILM convinced him that the Dykstraflex camera invented for the film made this unnecessary. Nevertheless, they added additional hull details to the Star Destroyer model. The 13-second opening shot was the first special effects piece ILM completed, and its success was an essential test for the Dykstraflex.