| Promoting DV Skills Shooting Techniques |
| STANDARD PAN NEVER X LINE TRACK CONVERSATION OVER-SHOULDER 2 CAM-SHOOT TRANSITION Motion Capture |
Since the 1980s digital video has been used to capture three-dimensional human motion for research, medicine, sport, engineering, game development, and film.
Motion Capture is used to understand
the gait cycle of a child, the action of an Olympic athlete,
the movement of a ostrich, to visualize engineering design, or
to capture 1000s of moves for video games, and motion of the skeletons in
the film Pirates of the Caribbean and the actors in Polar Express.
Each subject has many reflective "cats eyes" markers strapped to their joints.
All the camera units shine light that the markers reflect back to the camera.
As the subject moves then two cameras can locate each reflector in 3D.
However 3 or more cameras increase the accuracy of the motion paths.
The largest motion-capture lab has 256 cameras.
Motion Capture Units High-power strobes illuminate the reflective markers. Infrared - emits no visible light, allowing cameras to be less conspicuous. Visible Red provides the highest power and longest range. 
These cameras use four-mega-pixel technology. The cameras can record 2352x1728 full frame greyscale pixels at speeds of up to 160 frames per second. On-board image processing allows marker data to be processed close to the sensor in real time. Using high-resolution greyscale images, the markers are easily identified and their position feed out to a system computer. Other systems then take the marker data to apply hero, robot or villain skins to true human 3D motion. Virtual Reality goggles can integrate the actor into any environment, and so increase the realism or synchronise their motion.
The first secondary school to install a Vicon motion capture system was McKinley in Washington DC USA. 
Extracts and images by kind permission of ViconPeak |
