So I took the maps I had and I started playing with them in illustrator - trying to fit one to another - and after several minutes realized that I wasn't making any progress. What i was doing was what everyone was doing: eyeballing it. What was needed was a statistical or unbiased approach.
This got me thinking about that oh-so-expensive piece of GIS software - ArcGIS 10. Within its labyrinthine menus and windows was the ability to georeference one map to another. Georeferencing is the art (science?) of fitting one map to another by matching individual points on each map. Get a whole bunch of points on map A, match em' to map B and let the software stretch and manipulate the A to fit onto B. The more points, the better the fit.
I started with two points - the top and bottom of Lake Hooktongue (Fig 1). With these, I was able to get a decent vertical fit. Lake Hooktongue is, i think, the most exactly drawn feature on each map, so it makes sense to start there. Having done that, its also apparent that problems begin. The Kingmaker map is very stretched out along the east-west (x) axis. The map goes almost to the city of Pitax in the west and Lakes Candlemere and Tuskwater are far too east to correlate. Already, we can see that if we want to keep something as simple as hex integrity intact we have to sacrifice something.
|Figure 1: Georeferencing using two points (the top and bottom of the Hooktongue Slough). You should be able to click on it and it will enlarge in a pop up.|
However, note that none of the green and red crosses match up. If the points really were georeferenced they would overlap and there would be no blue lines connecting them. All those blue lines are error and its not just error in one direction, its error in several.
|Figure 2: Georeferencing with multiple points but allowing for some error.|
|Figure 3: Resolving as much of the error as I could from Figure 2.|
Postscript: I never used Rostov as a data point. When I examined its location on each map, I realized that it had been misplaced on one map (or the other). Going forward I will use the Kingmaker location because that is integral to the AP.