The orthographic projection is a specific type of map projection used to depict the Earth's surface, creating a realistic, three-dimensional appearance as viewed from a distant point.
Understanding the Orthographic Projection
Based on the provided reference, the orthographic projection is defined as an azimuthal perspective projection, projecting the Earth's surface from an infinite distance to a plane.
Let's break this down:
- Azimuthal Perspective Projection: This means the projection is centered around a specific point on the globe, and all points on the Earth are projected onto a flat plane from a single viewpoint.
- Projecting from an Infinite Distance: Unlike other perspective projections that might simulate views from low Earth orbit or closer, the orthographic projection simulates viewing the Earth from an extremely (infinitely) distant point. This is similar to how distant objects appear parallel to the eye.
This unique perspective results in a map that shows a hemisphere (or slightly less) of the Earth, with features appearing smaller and more compressed towards the edges, much like looking at a physical globe.
Characteristics and Uses
The defining characteristic of the orthographic projection is its visual effect. It gives the illusion of a three-dimensional globe. Because of this realistic appearance, it is often used for illustrative purposes rather than for accurate measurement of large areas, as shapes and areas are distorted towards the edges.
Common applications include:
- Used as an inset map within larger maps to show the location of the main map area on a globe.
- Ideal for pictorial views of the Earth from space, offering a visually compelling representation.
While it excels at providing a realistic global view, it's important to note that areas and shapes away from the center point are significantly distorted, making it unsuitable for navigation or precise area calculations across the entire projected surface.
