Map Scale and Effective Resolution
The traditional paper map is accurate to the width of a line, 0.5 mm. When paper maps are digitized, their accuracy transfers to the digital data. Some digital data sets may be created with better source materials, but because of the scale at which they are intended to be displayed, the number of points digitized, the care with which they are selected, and the number of decimal points carried may only be good enough for the intended scale.
|Scale||Effective Resolution (m)||Data Set|
|1:100,000||50||Original TIGER data|
|1:250,000||125||1ºx2º quadrangle, JOG|
|1:2,000,000||1000||US National Atlas|
Approximate conversions, degrees to metric.
Last revision 1/22/2014