Projections

"All maps lie flat, And all flat maps lie"

Mercator Projection

The REAL Mercator Map

• The Mercator Projection is a good example of how we've become naturalized to a view of the world that is actually distorted and abstract

• Mercator distorts AREA but not SHAPE

Human body, Mercator style

• In the process of transforming a geoid into an actual sphere which can be transferred onto a flat (planar) surface, there is much that is distorted.

• All meridians and parallels are transformed

• All human and physical earth features are transformed

3 Projection Families

Planar

Conical

Cylindrical

What distortions occur within each type?

Which one to use?• It depends on the application

• You will always give up shape to preserve area, or vice versa. You cannot have both

• Equal Area - area remains constant on map

• Conformal - angular relationships from point preserved

• Equidistant - distance from one point to all others is correct

• Compromise - somewhat right, yet all wrong

Equal Area Good for mapping themes

Peters projection

Lambert Azimuthal

Conformal MapsUseful for navigation as straight lines on the map are

constant compass bearings in the real world

Mercator Projection

Equidistant MapsUseful for plotting travel, such as for direct air routes

from a certain point

Orthographic Projection

Compromise ProjectionGood for non-cartographic people

Robinson Projection

Dymaxion Projection

Interrupted Projection