Certified Photogrammetrist Camera Calibration & Sensor Geometry

Question 1

What is the principal point in camera calibration?

Accepted Answer

The point where the optical axis intersects the image plane

Answer

The principal point is where the optical axis intersects the image plane, representing the foot of the perpendicular from the perspective center to the image plane.

Question 2

Which distortion model parameter primarily describes symmetric radial lens distortion?

Accepted Answer

K1 radial distortion coefficient

Answer

K1 is the primary radial distortion coefficient that describes symmetric, rotationally symmetric distortion measured from the lens center outward.

Question 3

What does interior orientation define in photogrammetry?

Accepted Answer

The geometric relationship between the image plane and the perspective center

Answer

Interior orientation defines the geometric relationship between the image coordinate system and the perspective center, including focal length, principal point location, and lens distortion parameters.

Question 4

In aerial photography, fiducial marks are used primarily to:

Accepted Answer

Define the image coordinate system

Answer

Fiducial marks are reference points etched into the camera's focal plane that define the image coordinate system and allow transformation from scanner to image coordinates.

Question 5

What is the calibrated focal length (CFL) in photogrammetry?

Accepted Answer

The focal length value that minimizes the overall effect of radial distortion across the image

Answer

The calibrated focal length is the value that minimizes the overall effect of radial lens distortion across the image format, and may differ slightly from the manufacturer's specification.

Certified Photogrammetrist Practice Test

Certified Photogrammetrist Practice Test

Certified Photogrammetrist Camera Calibration & Sensor Geometry