Georeferencing of historical map images involves assigning spatial information so that they align with real world geography. The essential process typically consists of adding control points to an historic map that have a real-world location; once there are sufficient control points, the historic map can be transformed so that it correctly aligns with geographic reality (Fleet et al., 2012).
This maptab you can load the corresponding geodata.
After more than 30 map enthusiasts located 912 maps with about 24,000 control points in the first project phase in 2016, more than 2,000 maps from GeoPortOst II have got now georeferenced as well.
In a short period of time, numerous volunteers have set many control points and have assigned even difficult maps with their geography.
Many thanks to all participants for their great commitment and the impressive result – in particular to the three top contributors Tucker Jones, Georg Zimmermann and Dominik Stoltz!
In addition to georeferencing, GeoPortOst offers numerous attractive features for working with the maps:
This map you will find the following offers:
Overlay & compare you will find the following offers:
Overlay & comparewindow and compare them directly or connect them.
Swipe modeto compare the map with today’s terrain.
Spy glassyou can focus on individual map sections.
Georeference a Random Map), you will be assigned a map at random. In the application, the historic map will appear on the left; a modern map will appear on the right.
Georeference this Mapunder the map image in the main window. This takes you to Georeferencer for your map.
Find a place-symbol (magnifying glass) at the left if necessary. Click on the
This maptab for more information. In some cases, it may be useful to consult historical gazetteers, which you can access in the Map Guide.
clippingthe borders (see video instructions).
Savebutton down right when you are finished. Now, you cam see the overlay of the georeferenced map.
Transcribe), for example, to indicate current place names or to clarify legends that are difficult to read.
Coordinatescontrol, add more control points or go on to the next map.
Thank you! The map is now georeferenced and you can use other functions for editing, analysis or comparison.
This mapyou will find the button
Open in GeoEditoron the right. Here you can draw on the map, mark borders, define polygons and save your editing as png.
This mapyou will find the button "Overlay & Compare" on the right. Here you can select different views (
Spy glass) on the map. Choosing
Gridyou can compare different maps. You can use the menu in the right frame to create a personal map selection and upload your own maps (
My private maps), search the entire GeoPortOst collection (
GeoPortOst) or access other maps from OldMapsOnline (
Enjoy and thank you!
For questions/remarks please contact us:firstname.lastname@example.org