🗺 Map Georectification
①Calibrate – choose projection and add Ground Control Points (GCPs). ② Compute – fit pixel→coordinate transform. ③ Query – click anywhere to get lat/lon coordinates.
Map Projection
Albers Equal Area – standard for US geological/geographic maps.
Click on lat/lon grid intersections visible on the map (e.g. where the 40°N line meets the 100°W line).
Need ≥ 3 points, ideally spread to the corners.
Add Control Point
Click a known location on the map, then enter its coordinates:
Add ≥ 3 control points, then click Compute.