How Does Image Resolution Relate To Map Scale? First, 20cm imagery is not the same as 1:20 map scale. Maps are created with mix and match combinations of data sources. Each source may be fine on its o...

1:10,000 in southern Ontario, meaning each 24″ x 30″ map sheet covers 5km x 5km, or, 1:20,000 for northern Ontario, meaning each sheet covers 10km x 10km.