File talk:Southeast Missouri Lead District - subdistricts map.svg
Scale[edit]
Because the scale bar has been changed, a brief discussion on how the correct scale was derived is in order. This map uses a UTM projection, so linear scale is constant. The southern boundary of Franklin County was measured in a GIS program using the same digital vector data (shapefile) used in this map. The line was measured to be 32 miles. The same line was measured in Inkscape, the SVG program used to finish this map, and the resulting number of pixels was used to calculate the pixels-per-mile scale at the magnification level being used. That was used to draw a temporary 60-mile line to use as a guide for the scale bar shown.
The original error occured because a 50-km scale bar was sized in the same manner to match a 50-mile length. It's an error that NASA would understand. I'm confident that the scale shown now with the 100-km/60-mi scale bar is accurate, and the information above should be sufficient for anyone interested to double-check the results. Kbh3rd (talk) 03:26, 29 March 2010 (UTC)
