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Flashcards in Exam 2 Deck (21):
1

Vertical photographs are taken from an aircraft with the optical axis of the camera what?

Nearly vertical as possible

2

How many degrees are tilted photographs?

Less than one and seldom more than three

3

Equations for vertical and tilted photographs are developed assuming what?

Truly vertical photographs

4

Tilted photographs may be analyzed using what?

The relatively simple truly vertical equations

5

The first assumption in the chapter on vertical photographs is that the photographs are what?

Truly vertical

6

The second assumption in the chapter on vertical photographs is that the photo coordinate axis system has its origin at the what?

Photographic principal point

7

What is the difference between the photographic principal point and the indicated principal point?

The photographic principal point is calibrated and really in the center of the photo ; the indicated principal point is where the fiducial lines cross

8

The third assumption in the chapter on vertical photographs are that all photo coordinates have been corrected for what?

Shrinkage, lens distortion, and atmospheric re-fraction distortion

9

What is map scale?

The ratio of a map distance to the corresponding ground distance

10

What is the scale of a photograph?

The ratio of the distance on the photograph to the corresponding distance on the ground

11

Is 1:1000 a larger scale than 1:5000?

Yes

12

Lowercase letters are found on the what?

Photograph

13

Uppercase letters are found on the what?

Ground

14

What is The function of a scale factor?

Converting from unitless in AutoCAD to mm on the photo and to get meters on the ground

15

Arbitrary coordinates can be transformed if at least what?

Two of the points have coordinates in a control system such as state plane

16

The effect of relief displacement is most apparent on what?

Tall vertical objects but it exists for points on a rolling terrain surface as well

17

The most critical error source in relief displacement is what?

Photo measurement , particularly relief displacement parameter D

18

equation 1

Q image thumb

used to get ground coordinates from vertical photo measurements

19

equation 2

Q image thumb

Scale of a vertical photo over flat terrain

20

equation 3

Q image thumb

relief displacement formulas

21