Problem of the Week: Photogrammetry Problems: General Definitions

The termfiducial marker, as it is used in photogrammetry, is best defined as

A. one of the (usually) two images on a photograph that define the axis of the tilt
B. a premarked target set on the ground to balance the stereo model
C. one of the (usually) four objects connected to the camera's interior that form images on the negative as each photograph is taken
D. the plane that defines the camera's focal length

Solution:

According to the law of reversibility of light paths, the effect of lens distortion in the camera is reversed in the plotting instruments if identical imperfections exist in both lens systems.

The answer is A.

This is problem 2 (8-1) from the NEW third edition of “Surveying Solved Problems for the FS and PS Exams” by Jan Van Sickle, PLS (formerly "1001 Solved Surveying Fundamentals Problems"). Reprinted with permission from “Surveying Solved Problems for the FS and PS Exams” by Jan Van Sickle, PLS (2008 Professional Publications Inc.). For details on this and other FLS exam-prep books, call 800/426-1178 or visit www.ppi2pass.com