Position the "eye" at the center of the earth for the Gnomonic projection.[br]- All great circles are projected to straight lines[br]- Used for plane navigation[br]- Distortion is very great as you get far from the pole[br][br]Position the eye at the south pole for the Stereographic Projection.[br]- Conformal (preserves angles/shapes)[br]- Used as the starting point for special projections based on holomorphic functions, e.g. Pierce Quincuncial, GS50, etc.[br][br]Position the eye infinitely far away for the Orthographic Projection[br][br]Position the eye above the north pole for a Near-Side Perspective Projection[br][br]Position the eye below the north pole for a Far-Side Perspective Projection[br][br]Change the spacing of parallels in the projection to satisfy equal-area or equidistant criteria.