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 geometric center of the image frame

Answer

The midpoint between two fiducial marks

Answer

The projection center of the lens

Question 2

Which distortion model parameter primarily describes symmetric radial lens distortion?

Accepted Answer

K1 radial distortion coefficient

Answer

Affinity coefficient

Answer

Decentering coefficient P1

Answer

Principal point offset

Question 3

What does interior orientation define in photogrammetry?

Accepted Answer

The geometric relationship between the image plane and the perspective center

Answer

The position and attitude of the camera in the world coordinate system

Answer

The spatial relationship between overlapping images

Answer

The transformation from pixel to ground coordinates

Question 4

In aerial photography, fiducial marks are used primarily to:

Accepted Answer

Define the image coordinate system

Answer

Measure ground control points

Answer

Calibrate the onboard GPS receiver

Answer

Determine the aircraft flight altitude

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 manufacturer's nominal specified focal length

Answer

The distance from the rear nodal point to the film plane

Answer

The focal length measured when focused at infinity

Question 6

Which laboratory calibration method uses precision optical collimators to simulate distant targets at infinity?

Accepted Answer

Goniometer calibration

Answer

Test field calibration

Answer

Stellar calibration

Answer

On-the-job self-calibration

Question 7

The image scale (s) of a vertical aerial photograph with focal length f taken at flying height H above datum is expressed as:

Accepted Answer

s = f / H

Answer

s = H / f

Answer

s = f × H

Answer

s = f + H