Tilted Perspective Projection

 

A true "view from space" projection. Whenever the Earth is photographed from space, the camera records the view as a perspective projection. If the camera precisely faces the center of the Earth the projection is Vertical Perspective. If the camera does not precisely face the center of the Earth the projection is a Tilted Perspective.

 

Perspective projections are neither conformal nor equal area.  Vertical Perspective projections are azimuthal; Tilted Perspective projections are not.

 

Scale

 

Scale is accurate only at the center for Vertical Perspective. Directions from the center are true for the Vertical Perspective for the sphere and for the polar ellipsoidal form.

 

Distortion

 

No distortion at the center for Vertical Perspective. Considerable distortion near the edges of the projection and throughout Tilted Perspective projections.

 

Usage

 

Used for pictorial views of the Earth as seen from space. Vertical Perspective is used for weather maps issued by the U.S. National Weather service as seen from geosynchronous satellites near the Equatorial plane. Tilted perspective in the ellipsoidal form is used for Space Shuttle Large Format Camera images and other photographs.

 

Limitations

 

Use only for a single hemisphere.

 

Origin

 

Known by Greeks and Egyptians in ancient times.

 

Limiting Forms

 

Orthographic, Stereographic and Gnomonic projections are special forms of the Vertical Perspective.