Near-sided perspective

The near-sided perspective projection simulates a view from a height \(h\) similar to how a satellite in orbit would see it.

Classification

Azimuthal. Neither conformal nor equal area.

Available forms

Forward and inverse spherical projection

Defined area

Global, although for one hemisphere at a time.

Alias

nsper

Domain

2D

Input type

Geodetic coordinates

Output type

Projected coordinates

Near-sided perspective

proj-string: +proj=nsper +h=3000000 +lat_0=-20 +lon_0=145

Parameters

Required

+h=<value>

Height of the view point above the Earth and must be in the same units as the radius of the sphere or semimajor axis of the ellipsoid.

Optional

+lon_0=<value>

Longitude of projection center.

Defaults to 0.0.

Note

The default convention is to interpret this value as decimal degrees. To specify radians instead, follow the value with the “r” character.

Example: +lon_0=1.5708r

See Projection Units for more information.

+lat_0=<value>

Latitude of projection center.

Defaults to 0.0.

Note

The default convention is to interpret this value as decimal degrees. To specify radians instead, follow the value with the “r” character.

Example: +lat_0=1.5708r

See Projection Units for more information.

+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.