CARIS HPD : CARIS Geomatics Reference Guide : Map Projections : Equidistant Conic (Simple Conic)
 

Equidistant Conic (Simple Conic)

General

Used in atlases to show areas in the middle latitudes.

Good for regions within a few degrees of latitude and on one side of the equator. One example, the Kavraisky No. 4, is an Equidistant Conic projection in which standard parallels are chosen to minimize overall error.

Not conformal, perspective, or equal area.

A blending of Lambert Conformal Conic and Albers Equal Area Conic.

Directions

Reasonably accurate but distortion increases away from standard parallels.

Distances

True only along meridians and along one or two standard parallels.

Areas

Reasonably accurate but distortion increases away from standard parallels.

Shapes

Reasonably accurate but distortion increases away from standard parallels.

Type

Conic.

Mathematically projected onto a cone tangent at one parallel or conceptually secant at two parallels

History

Prototype was developed by Ptolemy in the year 150 and improved by De l’Isle around 1745.

Note

Not directly supported. Maps must be transformed before being used.

(United States Geological Survey, n.d.)