Details zur Wahl eines Koordinatensystem

coordinates

A set of values represented by the letters x, y, and optionally z (elevation) or m (measure), that define an object's position within a coordinate system.

coordinate system

A reference framework consisting of a set of points, lines, and/or surfaces, and a set of rules, used to define the positions of points in space in either two or three dimensions. The Cartesian coordinate system and the geographic coordinate system used on the earth's surface are common examples of coordinate systems.

a reference system that locates a position in space and defines the relationships between positions. Coordinate systems enable individual datasets to be georeferenced to each other. The specification of a coordinate system is one of the initial steps in creating a new feature class or raster dataset.

There are several types of coordinate systems used to define the positions of points in space. The most commonly used coordinate systems include:

Cartesian coordinate system

A two-dimensional, planar coordinate system in which horizontal distance is measured along an x-axis and vertical distance is measured along a y-axis. Each point on the plane is defined by an x,y coordinate. Relative measures of distance, area, and direction are constant throughout the Cartesian coordinate plane. The Cartesian coordinate system is named for the French mathematician and philosopher Ren Descartes (1596-1650).

A system that allows a user to pinpoint any location on a map precisely and objectively by giving its two coordinates (x,y).

In imagery, a three-dimensional coordinate system where each axis is orthogonal, the scale in each direction is the same, and the reference for photogrammetry is earth stationary.

Spherical Coordinate System

In spherical coordinates, positions are defined using a radius, an inclination angle, and an azimuthal angle. This system is often used for celestial objects and phenomena.

geographic coordinate system

A reference system that uses latitude and longitude to define the locations of points on the surface of a sphere or spheroid. A geographic coordinate system definition includes a datum, prime meridian, and angular unit.

Projected Coordinate System (PCS)

A projected coordinate system (PCS) involves using a map projection to represent the Earth's 3D surface on a 2D plane. This is necessary because the Earth is a 3D object and representing it on a flat surface causes distortion. Different map projections are used to preserve specific qualities such as area, shape, distance, and direction, but it's impossible to preserve all four perfectly in 2D. For example, the Mercator projection distorts the area of landmasses, making countries near the poles appear larger than they are. The Web Mercator projection is a common example of a PCS, widely used in web mapping applications.

What About Local Coordinate Systems?

A local coordinate system optimizes for accuracy for a specific location. These are most often used by local governments, construction teams, and surveyors because the narrower the area a coordinate system needs to cover, the less distortion you need to account for on a global scale when projecting.

This is why we have thousands of coordinate systems — because they have been created and optimized to reduce distortion of the area, distance, shape, direction, or any combination of those within a certain location.

For example, DHDN for Germany is a local coordinate system.

• Ocean
• Ellipsoid
• Local plumb line
• Continent
• Geoid

EPSG ID

A coordinate system identification was created by the European Petroleum Survey Group. https://epsg.io/

Aktualisiert am: 30/07/2025