PS Photogrammetry & Remote Sensing

Question 1

The principal point in aerial photogrammetry is best defined as:

Accepted Answer

The foot of the perpendicular from the lens center to the image plane

Answer

The nadir point projected onto the photograph

Answer

The center of the exposure station above the ground

Answer

The average ground elevation within the photograph

Question 2

Relief displacement in an aerial photograph causes elevated objects to appear:

Accepted Answer

Displaced radially outward from the principal point

Answer

Smaller than their true planimetric size

Answer

Displaced toward the principal point

Answer

Uniformly shifted toward the low end of the terrain slope

Question 3

The photo scale at a ground point with elevation h above datum, where f is focal length and H is flying height above datum, is:

Accepted Answer

f / (H - h)

Answer

f / H

Answer

H / f

Answer

(H - h) / f

Question 4

The base-to-height (B/H) ratio in aerial stereoscopy is defined as:

Accepted Answer

The ratio of air base distance between exposure stations to flying height, controlling stereo height accuracy

Answer

The ratio of focal length to flying height

Answer

The ratio of forward overlap percentage to sidelap percentage

Answer

The ratio of photo footprint width to photo footprint length

Question 5

In aerial photography, a standard 60% forward overlap (end lap) is maintained primarily to:

Accepted Answer

Ensure complete stereoscopic coverage so every ground point appears in at least two consecutive photographs

Answer

Reduce the ground footprint of each individual photograph

Answer

Eliminate sidelap requirements between adjacent flight strips

Answer

Compensate for lens distortion at the edges of each photo

Question 6

An orthophoto differs from a standard aerial photograph because it:

Accepted Answer

Has uniform scale due to removal of relief displacement and camera tilt distortions

Answer

Is captured using near-infrared wavelengths only

Answer

Shows only man-made features with natural terrain removed

Answer

Is produced exclusively from satellite imagery at fixed orbital altitudes

Question 7

A longer focal length aerial camera, compared to a shorter focal length camera flown at the same height, produces:

Accepted Answer

A narrower angle of view and larger photo scale

Answer

A wider angle of view and smaller photo scale

Answer

A wider angle of view and larger photo scale

Answer

A narrower angle of view and smaller photo scale