Aerial View Maps

mathematics/geography related question?

The scale of an aerial photograph can be obtained by dividing the focal length of the camera (151.76mm) by thaltitude of the plane above the ground (approx 5290 metres). 1. what is the scale of the original aerial photograph, to the nearest 1000? 2. How far on the ground is 1mm on the air photo? (calculations needed)

Public Comments

1. Focal length = 151.76 mm Altitude above ground = 5290 m = 5,290,000 mm Scale = 151.76 / 5,290,000 = 1/34857.67 Scale is 1:35,000 (to the nearest 1000) 1 mm in photo is 35,000 mm or 35 m on the ground
2. 1. I'll take your word for it that the formula is correct. Scale is 0.15176 / 5290 = 0.0000286881 A scale written as a tiny fraction is inconvenient, so I usually press the reciprocal (1/x) button on the calculator, so I can write it as 1 in 34867 2. Writing it that way, it is easy to see that I multiply any distance on the photo by 34867 to get the distance on the ground. So 1 mm is 34867 mm, that is 34.87 metres.