Description of CRS - FR_NTF / FR_LAMB
AttributeEntry
CountryFrance
Country identifierFR
CRS identifierFR_NTF / FR_LAMB
CRS alias
CRS valid areaFrance
CRS scope
CRS remarks
Datum identifierNTF
Datum alias
Nouvelle Triangulation de la France
Datum typegeodetic
Datum anchor point
France, Paris, Pantheon,
Lat = 48°50'46.52" N,
Lon = 02°20'48.67" E
Datum realization epoch1898
Datum valid area
France
Datum scope
Datum remarks
Prime meridian identifierParis
Prime meridian greenwich longitude2°20'14.025" E
Prime meridian remarks0 grade Paris
Ellipsoid identifierClarke 1880 IGN
Ellipsoid alias
Ellipsoid semi major axis6 378 249.2 m
Ellipsoid shapetrue
Ellipsoid inverse flattening293.4660213
Ellipsoid remarks
Coordinate system identifierFR_LAMB
Coordinate system typeprojected
Coordinate system dimension2
Coordinate system remarks
Coordinate system axis namenorthing
Coordinate system axis directionNorth
Coordinate system axis unit identifiermetre
Coordinate system axis nameeasting
Coordinate system axis directionEast
Coordinate system axis unit identifiermetre
Operation identifierFR_LAMB
Operation valid areaFrance, with 5 different zones (I...Nord, II...Centre, IIE...Etendue, III...Sud, IV...Corse)
Operation scope
Operation method nameLambert Conformal Conic Projection with 1 standard parallel
Operation method name alias
Operation method formula
Lambert Conformal Conic Projection, in Hooijberg, 
Practical Geodesy, 1997, pages 133-139 
Operation method parameters number6
Operation method remarks
description parameters with longitude / latitude values in 
FR_Lamb are described in grades (gon) 
ellipsoidal coordinates in Datum NTF are all also in 
grades and refer to Prime Meridian Paris 
Operation parameter namelongitude grid origin for all zones
Operation parameter value
0 grade
Operation parameter remarks0 grade wrt Paris = 2°20'14.025" E wrt Greenwich
Operation parameter nameapplication area of zones
Operation parameter value
zone I:   53.5...57.0 grades N
zone II:  50.5...53.5 grades N
zone IIE: 45.9...56.5 grades N
zone III: 47.0...50.5 grades N
zone IV:  45.9...47.8 grades N
Operation parameter remarkszone I: = 48°09'00"...51°18'00" N zone II: = 45°27'00"...48°09'00" N zone IIE: = 41°48'36"...50°51'00" N zone III: = 42°18'00"...45°27'00" N zone IV: = 41°18'36"...43°01'12" N
Operation parameter namelatitude of origin / central parallel of zones
Operation parameter value
zone I:   55    grades N
zone II:  52    grades N
zone IIE: 52    grades N
zone III: 49    grades N
zone IV:  46.85 grades N
Operation parameter remarkszone I: = 49°30'00" N zone II: = 46°48'00" N zone IIE: = 46°48'00" N zone III: = 44°06'00" N zone IV: = 42°09'54" N
Operation parameter namefalse northing of zones
Operation parameter value
zone I:     200 000 m
zone II:    200 000 m
zone IIE: 2 200 000 m
zone III:   200 000 m
zone IV:    185 861.369 m
Operation parameter remarks
Operation parameter namefalse easting of zones
Operation parameter value
zone I:   600 000 m
zone II:  600 000 m
zone IIE: 600 000 m
zone III: 600 000 m
zone IV:  234.358 m
Operation parameter remarks
Operation parameter namescale factor of zones
Operation parameter value
zone I:   0.99987734
zone II:  0.99987742
zone IIE: 0.99987742
zone III: 0.99987750
zone IV:  0.99994471
Operation parameter remarks