2017 GIS in the Rockies presentation

1. Sharing Historical Maps
and Atlases in Web Apps
Aileen Buckley

2. The Goal
• Create an interactive online collection of maps that would include…
- Archival quality images of maps in the collection
- The ability to select, compare, and download the images
- The ability to share the collection with others
• …providing a rich and engaging online experience to increase the use of the
collection while at the same time archiving the maps.

3. USGS Historical Topographic Map Explorer
• Almost 186,000 maps
• Simple, intuitive web
application (app)

17. Bering, Chukchi, and Beaufort Seas Strategic Assessment: Data Atlas
• NOAA
• 99 maps
• 2 phases
• Maps, legends, text,
drawings

21. Topics
• Introduction
• Project Planning
• Map Examples
• Workflow
- Metadata
- Scanning
- Georeferencing
- Mosaic Dataset
- Image Service
- Web App
• Wrap Up
• Resources

22. Introduction

23. Types of Historical Maps
• Topographic maps
• Thematic maps
• Navigation maps
• Engineering drawings
• Atlas pages
National agencies, private companies, NGOs, …

24. Uses for Historical Maps
• Provide a record of past landscapes
• Record changes through time
• Provide a record of geographical knowledge or perceptions from a given
period of time
• Constitute a record of cartographic and printing technology
• Provide insights into the values, beliefs, and social structures surrounding the
creation of the maps
• However, the current presumption is that maps of any value are created in digital
form or are made available in digital form
Summarized by Baruth (2000) from Skelton (1972) and Harley and Woodward (1987)

25. Users of Historical Maps
• Preservation of map images
- Primarily librarians and curators of collections
• Access and utilization of geographic data and map images
- Librarians
- GIS analysts
- Scientists
- Historians
- Genealogists
- Many others . . . .
It is not possible to fully predict all users of published georeferenced maps

26. Application areas for
Historical Maps
• Land resource management
- Urbanization
- Forest plot perimeters
- Wetlands
- Agriculture
- Glaciers
- Land/water boundaries
- Political boundaries
• Historical analysis
• Navigation
• Adventure/exploration

27. Project
Planning

28. Defining the Project
• It’s best to conform to your organization’s mission and needs
• Do not expect you can digitize (scan and georeference) all the maps in your
collection (at least at the outset)
• Selection criteria:
- Should the maps be digitized?
- Are the maps in a suitable condition to be digitized?
- Are there any issues preventing distribution of the maps?
- Is the infrastructure and technical ability in place?
• Good planning and testing will ease and shape the scope of the project
• Preservation and/or restoration can be a by-product of digitization
• Determine how people may use the digitized maps
Modified from Janet Gertz, Columbia University Library

29. Maps in the Collection
• Single or small number of maps
• Duplicate maps
• Maps with varying map extents,
dates, map scales, formats,
themes, etc…
• Maps with interior content,
overedge areas, etc…
• Maps that are not oriented with
north at the top of the page
• Damaged maps

30. Yosemite
1909
1:125,000

31. Yosemite
1929
1:125,000

32. Yosemite
1948
1:125,000

33. Yosemite
1953
1:125,000

34. Yosemite
1953 (2)
1:125,000

35. Yosemite Valley
1958
1:24,000

36. Yosemite Valley
1958
1:24,000

37. Yosemite Valley
Floor
1934
1:2,400

38. Yosemite Valley
Floor
1934
1:2,400

39. Map Sheet
• The original paper map
Text

40. Map Extent
• What you want to see
in the web app
Text

41. Neatline
• What you (normally)
want hidden

42. Modified neatline
• Fits the true map extent
Text

43. Workflow

44. Metadata Maps (Scanned and
Georeferenced)
Folders for Large Collections
Mosaic Datasets
Master Mosaic Dataset
Image
Service
Web
Web app

45. Metadata

46. Metadata Content
• Information about:
- the map
- the control points used to georeference the map
• Metadata is used:
- to define the map extent (inside the collar)
- to create the mosaic dataset
- in the web map app

47. Creating the Metadata
• Inventory the maps
• (Scan and georeferenced the maps)
• Collect the required and desired information
• Compile the info in Excel format

48. Metadata

49. Metadata

50. Metadata

51. Metadata

52. Scanning

53. In-house or Contracting Considerations
• Range of options and services needed
• Technical infrastructure required
• Technology refresh
• Need for fixed cost per item to be digitized
• Capability to handle volume and specific
processing steps
• Staff availability and staffing costs
• Acceptance of risk
All considerations are especially true for scanning maps

54. Scanning Recommendations
• Scan resolution 400 to 600 PPI
• 24-bit for color, 8-bit for monochromatic
• Untiled .tif format
• Uncompressed, or LZW or JPEG (for ArcGIS)
• Scan “as is” without restoration
• No color tints or lightening of the image
• Include map collar
Greg Allord, Esri Contractor; Peter Becker, Esri

55. Georeferencing

56. Georeferencing the Maps
“Aligning geographic data to a known coordinate system so it can be viewed,
queried, and analyzed with other geographic data.
Georeferencing may involve shifting, rotating, scaling, skewing, and in some cases
warping, rubber sheeting, or orthorectifying the data.”
• Maps that are good candidates for georeferencing:
- Are constructed on a known projection
- Have a graticule consistently scaled over the entire map
Georeferencing definition from Esri GIS Dictionary

57. Control Points
• A. Full control
• B. Partial control
• C. No control

58. A. Full Control
• Full grid from corner to corner and uniform distribution of control points
• Example: Quadrangle maps

59. B. Partial Control
• Maps with control points, generally a grid but map corners are not labelled
coordinates
• Examples: Thematic maps and reference maps, such as country, state, or county
maps with irregular extents

60. C. No Control
• Maps without control points
• Files be georeferenced in ArcGIS
• “Fundamentals of georeferencing a raster dataset”
http://desktop.arcgis.com/en/desktop/latest/manage-data/raster-and-images/fundamentals-for-
georeferencing-a-raster-dataset.htm

61. Define the Correct Projection and Datum
• Check the coordinate system (datum) in which the map was printed
• Not the projection of the neatline
• Georeference in map’s coordinate system
• Maps are not printed in geographic coordinates
• Lines of longitude and latitude are not straight
Text
Map was printed in NAD 1927
Corner control points are in geographic coordinates,
but with the NAD 1927 datum
`
`

62. Georeferencing with ArcGIS
• Manually collect control
points
• Use another image or a
vector layer with a known
spatial reference
YouTube: Georeferencing in ArcMap Tutorial

63. Georeferencing Recommendations
• Set Files to Read Only, otherwise
ArcMap/Pro will update them
• Do not use Rectify!
• Use Update Georeferencing
- Will create file.AUX.XML
- Defines:
- Image and ground coordinates
- Transformation type
- Projection information
- Can always improve later
• Optimization (faster but may not be as accurate)
- Use corner control points (in the map’s datum)
- Check residuals using 1st Order (affine) transformation
- Set to Projective Transformation

64. Metadata Maps (Scanned and
Georeferenced)
Folders for Large Collections
Mosaic Datasets
Master Mosaic Dataset
Image
Service
Web
Web app

65. DEMO

66. Wrap Up

67. Review of What Was Covered
• Introduction
• Project Planning
• Examples
• Workflow
- Metadata
- Scanning
- Georeferencing
- Mosaic Dataset
- Image Service
- Web App
Text

68. Final Tips
• Remain true to the mission and goals of the agency
• Take as much time as is needed at the outset of a project to clearly define its goals
and outcomes
• Insist on the highest quality technical work that the institution can afford
• Build in costs and capabilities for long-term maintenance of the digitized materials
• Cultivate a high level of staff involvement for digital projects
• Cooperate with other institutions whenever possible to achieve the greatest benefits
• Share experiences and results with other institutions or agencies
From Handbooks for Digital l Projects: A Management Tool for Preservation and Access

69. Unused digital products might as well not exist.
Greg Allord, Esri Contractor

70. Resources

71. Resources
• Share the workflow with others, including…
- Modifications for general applicability to a wider audience
- Documentation, sample data, and metadata
- Support
• …enabling others to build their own collections and bring their archives to life.
• Image management workflows
- http://resources.arcgis.com/en/home/

72. Resources
• Documentation:
- Project planning
- Scanning
- Georeferencing
- Creating the mosaic dataset
- Creating the image services
- Creating the index map feature service
- Configuring the web map app
• Sample Data
• Tools and toolbox

73. abuckley@esri.com
@cartatesri
@mappingcenter
Greg Allord, Esri Contractor
Thank you!