fabric absorbed and reflected different types of light, and was eventually able to make Trinity's costume mercury-like and oil-slick to suit the character. For the Agents, their costume was designed to create a secret service, undercover look, resembling the film JFK and classic men in black. The sunglasses, a staple of the film's aesthetics, were commissioned for the film by designer Richard Walker from sunglasses maker Blinde Design. Visual effects The film is known for popularizing a visual effect known as "bullet time", which allows a shot to progress in slow-motion while the camera appears to move through the scene at normal speed. Bullet time has been described as "a visual analogy for privileged moments of consciousness within the Matrix", and throughout the film, the effect is used to illustrate characters' exertion of control over time and space. The Wachowskis first imagined an action sequence that slowed time while the camera pivoted rapidly around the subjects, and proposed the effect in their screenplay for the film. When John Gaeta read the script, he pleaded with an effects producer at Mass.Illusion to let him work on the project, and created a prototype that led to him becoming the film's visual effects supervisor. The method used for creating these effects involved a technically expanded version of an old art photography technique known as time-slice photography, in which an array of cameras are placed around an object and triggered simultaneously. Each camera captures a still picture, contributing one frame to the video sequence, which creates the effect of "virtual camera movement"; the illusion of a viewpoint moving around an object that appears frozen in time. The bullet time effect is similar but slightly more complicated, incorporating temporal motion so that rather than appearing totally frozen, the scene progresses in slow and variable motion. The cameras' positions and exposures were previsualized using a 3D simulation. Instead of firing the cameras simultaneously, the visual effect team fired the cameras fractions of a second after each other, so that each camera could capture the action as it progressed, creating a super slow-motion effect. When the frames were put together, the resulting slow-motion effects reached a frame frequency of 12,000 per second, as opposed to the normal 24 frames per second of film. Standard movie cameras were placed at the ends of the array to pick up the normal speed action before and after. Because the cameras