I have some vector files that come without projection. So I have to define my own projection in QGIS. The information that comes with the data reads as following:
Projection: Lambert Azimuthal Units: Meters Datum: None Parameters: 6370997.24063 (radius of the sphere of reference) 100 0 0.000 (longitude of center of projection) 45 0 0.000 (latitude of center of projection) 0.00000 (false easting (meters)) 0.00000 (false northing (meters))
The Lambert Azimuthal is an equal area projection. I tried to translate this into a projection definition as:
+proj=laea +lat_0=45. +lon_0=100. +x_0=0 +y_0=0 +datum=none +units=m +a=6370997.24063 +b=6370997.24063
But my data is still wrongly projected.