Position
If this option is selected, the camera position will be set to the respective feature position at a defined time (frame) in the animation (the vertex cluster will be moved accordingly so the perspective and footage still match). This mode is only designed for use with camera tracking.
The most commonly used option. The world origin is, for example, set to the respective feature.
Frame [-2147483648..2147483647]
If Mode is set to Camera to Position, this value can be used to define the time within the animation at which the animated, solved camera is set to the position of the respective feature.
P.X [-∞..+∞]
P.Y [-∞..+∞]
P.Z [-∞..+∞]
Modify these values if you don’t want to set the world origin (e.g., the camera) precisely to the respective feature and would rather use other coordinates.
Target
Drag the Null object to which the world origin (e.g., the camera) should be set into this field. Normally, this will be set automatically if you position the orange circle or if you select the Position Constraint command.