Dahnielson

What is motion control?

Simply stated, motion control are the art of making images by putting the motion picture camera on a rig controlled by a computer. So that every movement can be programmed, repeated over and over again, with so great accuracy that no difference between takes will be visible. But what use can this ability serve?

It is programmable, so you always know in advance where the camera will be in any given moment. And makes it easy to integrate CGI objects and other elements into a scene and plan ahead for it. All movements of the camera and the rig are controlled by a computer. The operator program the rig by making key positions for the rig on a timeline. The computer then calculates all the in-between increments of position of the move, just like keyframing in any 3D animation program.

It is precise, so you can navigate the camera and lens in high speeds without risking to crash any equipment. Or to do very tiny moves in the micro world, using a camera equipped with macro or endoscope lenses. And you need no motion tracking if you want to incorporate CGI objects into the shot.

It is repeatable, it means that on multiple passes, at any given film frame on a camera pass, the camera will be in an identical position to that of previous passes, regardless of the physical speed of movement of the camera. Where the movement of the camera is controlled by hand, it is virtually impossible to get an exact duplication of a previous take or repeat the movement. Traditionally, this problem has been solved by holding the camera in a fixed position, known as “locking off” the camera, and doing all visual effects that way. But with a camera in motion, shots become harder to tell if they are effects or not. And motion control do moving camera effects shot easier to integrate and conceive.

To conclude with the words of Mark Roberts: “So, what then is Motion Control? It is an essential production tool in the toolbox of filming techniques, which allows that extra depth of reality in many special effects shots.”