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How To: Geo-referencing Maps

We have recently started a map digitization project at the Robertson Library called the "Island Imagined".  There's a nice introduction to GIS and historic maps available from the David Rumsey website. We'd like to georeference the digitized maps when possible and a tool I've been exploring to accomplish this task is an open source GIS software package called Quantum GIS (QGIS).

I thought I'd share some of the basic steps used to georeference a map.

Here's a screenshot of my qgis setup. I've loaded a number of vector layers add a vector layer including the island map with the lot boundries and roads displayed. Vector layers are lines, points, shapes. Parish, lot, town or other boundary lines are handy when selecting points for georeferencing as are roads. I downloaded the GIS data for free from the PEI government website.

QGIS layout

 

To add the historic map (a raster layer) to your map you need to start the Georeferencer plugin.

Georeferencer plugin

 

More to come ...