The cartographer or mapmaker must select a projection which will result in a minimum of distortion in relation to the map theme or purpose, the amount of land area shown, and the portion of the earth s surface being represented on the map. Note that several of Dana's map projection examples are linked to relevant portions of this page. Each family is suitable for representing select areas of the globe. And each family allows for tangent and secant case or tangency with the globe. These and other projection concepts and principles are explained below.
Poster provides examples of numerous projection types with varied properties and suggested uses.
And as mentioned above, several of Dana's projections are linked to explanations below. The points on the spherical grid are transferred to the cylinder which is then unfolded into a flat plane. This family of projections are typically used to represent the entire world. When projected from the center of the globe with the normal aspect, the typical grid appearance for cylindrical projections shows parallels and meridians forming straight perpendicular lines. The spacing varies depending on the type of cylindrical projection.