Motion capture is something used often in many films to record the actions and performances of actors or objects when something is going to be computer animated. Some examples of films where this effect is used include Avatar, The Lord of the Rings: The Two Towers, The Polar Express and The Avengers for The Hulk.
Many people are more familiar with motion capture and its applications in film production, but motion capture is also used in sports and the military.
There are three main types of motion capture systems: mechanical, optical and magnetic. In all systems, the actor wears a special suit. In the mechanical system, that suit is covered in metal pieces that have sensors in the joints. Using the optical system, the suit is covered in reflective dots. In the magnetic system, the actor is covered in magnetic receivers.
Each system has their individual drawbacks and advantages. For example, the mechanical system doesn’t require special lighting but does require that the positions and final movements are determined using mathematical calculations. In the optical system, there are no cables connected to the suit and it is easier to determine the exact movement of the subject, but there can be interference from light nearby. The magnetic system is the most affordable and accurate, but the data is easily distorted by magnetic fields or nearby metal.
Motion Capture Software
There are many different brands of motion capture software, each with its own benefits and drawbacks. Some of the most recent technological developments in the motion capture industry include real-time motion capture, first used in The Lord of the Rings: The Two Towers.