Nadir point
Iso-centre
Principal point
All the above
Answer is Right!
Answer is Wrong!
The principal plane contains the nadir point, iso-centre, and principal point.
The nadir point is the point on the ground directly below the camera. The iso-centre is the point on the principal plane that is equidistant from the principal point and the nadir point. The principal point is the intersection of the optical axis of the camera and the principal plane.
The principal plane is a plane that is perpendicular to the optical axis of the camera and passes through the principal point. It is used to define the location of the image on the sensor.
The nadir point, iso-centre, and principal point are all important points in camera calibration. They are used to determine the orientation of the camera and the location of the image on the sensor.