ArcGIS Georeferencing Tool a quick how-to

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ArcGIS Georeferencing Toola quick how-to

• Useful for historical data analysis
• Contour or Isohyetal maps
• Georeference image
• Digitize data to create GIS dataset
• Analyze or geoprocess

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Scan desired image

• Selected image needs some reference information
  that can be identified
• Example counties, lat/lon, state boundaries, etc

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ArcGIS project

• Add boundary base layers
• counties, lat/lon, states
• View- Georefernce tool

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• Lat/Lon lines

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• Zoom to approximate image extent
• Drag-n-drop image
• Fit to display

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• Attempt to see boundary features from both image
  and base layers
• Adjust zoom as needed

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• Use tool to click and match features from Image
  to Map
• Auto-adjust snaps features together

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Image
Map
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Snapped image to map
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Map
Image
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• Continue process at selected areas across image
  until aligned as desired

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• Create new shapefile for editing

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• Digitize contours

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• Attribute features

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• New data set can be geoprocessed for further
  analysis

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Questions?