Steadicam and Camera Movement
Before steadicam the two options open to directors and cinematographers for a standard tracking shot were "The Dolly" which consisted of placing the camera on a wheeled support and moving it along rails or tracks to ensure the smoothness of movement . The Dolly shot is associated with big Film Studio style productions. But the Dolly ultimately restricts the path of camera movement to a fixed track and the inability of the dolly to track the camera into or out of a scene without revealing it's own track limits the impact of the 3rd dimension of depth on the shot.
The other option is "hand held", which has the advantage of opening up the camera's freedom of movement but this delivers a jerky, unstable shot. The latter became the trade mark of the cinema verite movement of the 1950's and 60's.
The Steadicam expands the moving shot further and allows smooth and unrestricted movement of single shots covering a number of perspectives over expanses of uneven terrain or in small confined spaces. It's a best of both worlds solution, the freedom of the handheld combined with the smoothness of a dolly.
The potential of the steadicam to insinuate the camera into the scene and place the audience within the story, strips away the two dimensional constraints of the frame and diminishes the distance between the audience and the subject. Add this to the ability of the steadicam to perform long continuous scenes, without the distraction of edits, and the full emotion and drama of a scene is heightened, taking the viewer on a real time journey and drawing them even closer to the characters and story.
To achieve a continuous shot, without the distraction of cuts, requires a great deal of ability, concentration and rehearsal from everyone involved in the production. All members of the cast and crew must perform a number of precisely timed actions that culminate in a near perfect sequence that can intimately involve the audience.
A successfully choreographed steadicam shot has great impact, it also has the additional benefit because it saves time re-setting camera and lights for numerous alternative shots.