I try to georeference a topographic diagram (scale 1:5000) using a satellite image, already georeferenced on Greek Grid Coordinating System. The total error is about 2 to 3 meters. I noticed that by changing the transformation at the link table, from 1st order Polynomial to 2nd or even 3rd, the error is minimized. Is that a valid way for a proper georefernce in order to set the topographic diagrams on the right place on earth?
