.. _ScalingAndPhotogrammetry:

Scaling and Photogrammetry
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Homework Content
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Equations and Assumptions
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Assume the focal length 'f' to be 6 inches or 152 millimeters.


Scaling Relationships
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.. math::

    \frac{d}{D} &= \frac{1}{\textrm {scale factor}} = \frac{f}{H}

    d &= \textrm {map distance}  \\
    D &= \textrm {ground distance}  \\
    f &= \textrm {camera focal length}  \\
    H &= \textrm {flying height}  \\



Problems
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Show all your work clearly with all units and in detail, leading up to the answer:

1)	An air photo has a scale of 1:50000.

    If a given map length is two inches, what is the corresponding ground distance in:

      a) inches
      b) feet
      c) meters

    What is the flying height of the airplane in:

      d) feet
      e) meters

    If a building has map length of two inches and map width of three inches, what is the ground (actual) area of the building in:

      f) square inches
      g) square feet
      h) acres


2) Repeat problem one if the scale of the air photo is 1:82000.



Metadata
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| Title:Scaling and Photogrammetry
| CreationDate:06/20/2013
| SoftwareUsed:None
| SoftwareVersion:None