Bullet Time

Bullet Time — also known as Time Slice — freezes a motion and allows the camera to seemingly travel through the frozen moment. The trick lies not in one fast camera, but in many: a ring of dozens of still or cine cameras is set up along the desired path and triggered almost simultaneously. The individual frames are then assembled into a sequence — the viewer circles a frozen event.

Origin

The technique became widely known in 1999 through The Matrix, which also gave the effect its name. It was not invented there: Tim Macmillan was already working with Time Slice setups in the 1980s, and Michel Gondry used the technique in music videos and commercials in the mid-nineties. The Matrix usage was popularization, not the origin.

Setup

Three things are crucial: the geometry of the rig, because the camera positions define the virtual path; the exact synchronization of the triggering; and clean alignment of the individual frames in post-production, because even slight deviations in height or angle become visible as judder. Previously, this was purely a still photo array setup. Today, many identical cine cameras are often used, allowing for intermediate motion and deliberate time shifts — the motion therefore doesn't have to freeze completely, it can slow down.

Today

With affordable, identical compact cameras, the setup has moved beyond blockbuster budgets. An array of several dozen bodies has become achievable for an advertising production; the effort has shifted from camera purchase to rig construction, synchronization, and post-production.