Chamberlin Trimetric

Classification	Miscellaneous
Available forms	Forward spherical projection
Defined area	Global
Alias	chamb
Domain	2D
Input type	Geodetic coordinates
Output type	Projected coordinates

proj-string: +proj=chamb +lat_1=10 +lon_1=30 +lon_2=40

Parameters

Required

Note

Control points should be oriented clockwise.

+lat_1=<value>

Latitude of the first control point.

+lon_1=<value>

Longitude of the first control point.

+lat_2=<value>

Latitude of the second control point.

+lon_2=<value>

Longitude of the second control point.

+lat_3=<value>

Latitude of the third control point.

+lon_3=<value>

Longitude of the third control point.

Optional

+lon_0=<value>

Longitude of projection center.

Defaults to 0.0.

+R=<value>

Radius of the sphere, given in meters. If used in conjunction with +ellps, +R takes precedence.

See Ellipsoid size parameters for more information.

+x_0=<value>

False easting.

Defaults to 0.0.

+y_0=<value>

False northing.

Defaults to 0.0.