From Analog to Digital

Phase 1: Determining Projection

With the image files in hand, the work of tethering them to latitude and longitude began. In order to put the historical maps in dialogue with modern basemaps such as Google Satellite or Open Street Map, we had to determine the scale and projection of the atlas. This was not a task for the faint of heart. It turned out that the atlas sheets were executed not only at different scales, but in different projections. (This makes sense given the longitudinal breadth of the empire, but it introduced quite a few wrinkles.) Our choice was to follow the lead of Piadyshev's team and work from an equidistant conic projection, customizing the central meridian to fit the Eurasian landmass.

Phase 2: Georeferencing the Sheets

The georeferencing process involves creating links between specific locations on a basemap, and related locations from an image file. Once a certain number of links are created, GIS can run an algorithm that assigns spatial coordinates to the entire surface of the image.   

Phase 3: Creating a Mosaic

Projected Coordinate System: Equidistant_Conic

Projection: Equidistant_Conic
false_easting: 0.00000000
false_northing: 0.00000000
central_meridian: 37.50000000
standard_parallel_1: 47.00000000
standard_parallel_2: 62.00000000
latitude_of_origin: 0.00000000
Linear Unit: Meter

Geographic Coordinate System: GCS_Geographic Coordinate System
Datum: D_WGS84
Prime Meridian: Greenwich
Angular Unit: Degree

Phase 4: Assessing "Accuracy"

The atlas sheets were produced at various scales and in varying projections. The east and west mosaics have been produced and georeferenced with extraordinary care and expertise by MadMappers. As a result the derived layers offer the user a remarkably accurate view of the space of the Russian Empire as represented on the most sophisticated atlas of the early 19th century. Careful users will recognize that the historical representation of space does not correspond neatly with that produced using modern satellite imaging and cartographic science. The 'distortions' or 'inaccuracies' of the Piadyshev atlas are minimal given the scope and complexity of the georeferencing process; moreover, they present users with an opportunity to explore central issues in the history and science of map production.