Ground principal point
Ground plumb point
Iso-centre
Perspective centre
Answer is Right!
Answer is Wrong!
The correct answer is: Ground principal point.
The ground principal point is the point on the ground where a vertical line through the optical center of the camera lens intersects the ground. It is also known as the nadir point or the plumb point.
The ground principal point is important in photogrammetry, which is the science of making measurements from photographs. It is used to calculate the scale of a photograph and to correct for lens distortion.
The other options are incorrect.
- Ground plumb point is the point on the ground directly below the optical center of the camera lens.
- Iso-centre is the point on the ground where the optical axis of the camera lens intersects the ground.
- Perspective centre is the point on the ground where the line of sight from the camera lens intersects the ground.