Geography 12: Maps and Mapping - University of California ...kclarke/G12/lectures/Lecture17.pdf ·...
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1 Geography 12: Maps and Mapping Lecture 17: New methods and Issues for Heights on Maps Base line
Transcript of Geography 12: Maps and Mapping - University of California ...kclarke/G12/lectures/Lecture17.pdf ·...
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Geography 12: Maps and MappingLecture 17:
New methods and Issues for Heights on Maps
Base line
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Triangulation and Plane Table
US Coast and Geodetic Survey: 1937 national coverage
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Triangulations: WGS70
Post WWII Air photographs
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Principal Point
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Radial displacement around nadir
Relief Displacement
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Height from displacement
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Reference axes
Orthorectification
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Orthorectified
Buildings easy, terrain hard!
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Unless, there are two images
Stereo geometry (Conjugate PP)
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Flight line geometry/overlap
Height from parallax
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Flight planning map
Analog photogrammetry
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Softcopy photogrammetry
Wild Heerbrug BC2Analytical Stereoplotter
Intergraph Workstations
How SAR works
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Terrain Model from IFSAR (Hailey, ID)
IFSAR DEM
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SAR from Space
SRTM: Global topo map
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NOAA Southern Cal. IFSAR viewer
IFSAR: Thousand Oaks, CA
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How Lidar works
LIDAR first and last pulse
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LIDAR terrain detail
Critical height issue: Sea Level
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Summary
• First generation topographic mapping used triangulation and plane table
• Second generation used stereo photogrammetry
• New generation uses IFSAR and LIDAR• Unprecedented accuracy• What surface to map?
