115AL Extra Credit Problems (see Lab 1 for reference)
* Due on or before the day of the midterm
 
Put only answers on this page (in the appropriate units), attach separate page(s) with your work; this includes which formula(s) you used, the math and how you did your unit conversions etc. but it does not have the be perfectly neat, only legible      *no work = no credit

UCSB/IV in 1954 (next page)

1) determine the aircraft altitude given a six inch focal length using the scale given above and the appropriate formulas from Lab 1

___________ ft
 ________ m

  2) if you have no knowledge of the camera focal length, but you knew the aircraft was flying at 10,000 feet, then what camera focal length must be used to get
___________ in
 ______ mm


 3) 2 parts; measure the length marked by the thin white line on the image below with a rule. The real world length is 1500 feet. what is the scale of this image? (you have to print it out and measure it)

One cm on this image is;

  a) how many miles (5,280 feet = 1 mile)
  c) how many feet
  b) how many kilometers
  d) how many meters

4) Calculate the area of the white box (thick white lines) on the image below (e.g. you measure it)
- the real world length (GD) of the road segment along El Colego from where it intersects Storke to the West Entrance of Campus is 1500 ft., you will need to calculate the scale of this image in order to figure-out the real world area encompassed by the white rectangle.
a) in square feet     ______ft2 
b) in square miles     ______mi2
c) in acres    ______ac
d) in square meters     ______m2
e) in hectares     ______ha
f) in square kilometers       ______ km2

5. For a photo with a RF of 1:10,000 determine the following:
A. The number of feet, meters and yards on the ground per inch on the photo.

___________ ft
 _________ m
___________ yards
B. The number of acres and square miles on the ground per square inch on the photo.  (Hint:  there are 43,560 square feet per acre and 5,2802 square feet in a square mile).
___________ ac
 _________ mi2
C. The number of square kilometers and hectares on the ground per square inch on the photo  (Hint:  there are 230.4 acres per square kilometer 1ha = 10,000m2).
___________ km2
 _________ ha
6. You want to contract for 1:10,000 scale photography of your fields with an aerial camera and a 90 mm focal length lens.  How high should you specify for the plane to fly above mean ground elevation?
___________ ft
 _________ m
7. A road segment shown on an aerial photograph can be located on a 1:24000 topographic map (a standard USGS 7.5' quad).  If the measured distance is 50 mm on the map and 95 mm on the photograph, what is the scale (RF) of  the photograph?

8. Scales of vertical photographs change constantly with variations in terrain elevation (topography).  Using the appropriate formula and some simple algebraic manipulations, substantiate the previous statement by showing how scale changes with decreasing and increasing elevations from the datum elevation.  The aircraft is flying at 9,000 feet above mean sea level (MSL), the elevation at Point A is 5,000 feet and 2,000 feet at Point B.  The camera focal length is eight inches.  What are the RFs at  Points A and B?