By selecting this section the coordinate operation will perform a conversion of coordinates. A conversion represents an operation with the values of coordinates between two coordinate reference systems that have the same datum.

Conversion type

Select the type of conversion from the following options:

(φ, λ, h) → (X, Y, Z) or (φ, λ) → (X, Y, Z)

Conversion from geographic coordinates to geocentric Cartesian coordinates. For this conversion it can be chosen if the ellipsoidal elevation h is used or not in the calculation. If it is not used then it is considered that h=0.000, the geographic 2D case.

(X, Y, Z) → (φ, λ, h) or (X, Y, Z) → (φ, λ)

Conversion from Cartesian geocentric coordinates to geographic coordinates. For this conversion it can be chosen if the ellipsoidal elevation h is calculated or not. If it is not calculated then h=0.000, geographic 2D case.

(φ, λ) → (N, E)

Conversion from geographic coordinates to projection plane coordinates according to the selected projection.

(N, E) → (φ, λ)

Conversion from projection plane coordinates to geographic coordinates according to the selected projection. For the projections that aren’t reversible this option isn’t available.

Datum on which the conversion is made

Ellipsoid short name

Set the short name of the ellipsoid.

Button Select ellipsoid...

Choose an ellipsoid from the list of predefined ellipsoids.

Semi-major axis

Set the value of the major semi-axis.

Inverse flattening

Set the value of the inverse flattening. To define a sphere, introduce the value 0.000. For projections that work only on spheres, this box is disabled; in this case the value of the inverse flattening is considered 0.000 for the projection that uses this value.

Prime Meridian

Select the prime meridian of the used datum. If the prime meridian differs from Greenwich, the conversion from geographic coordinates (φ,λ,h) to Cartesian geocentric coordinates (X,Y,Z) is made always relative to the Greenwich zero meridian and for the inverse conversion the longitude calculated from (X,Y,Z) is rotated in order to return to the selected prime meridian.

Calculate the coordinates on the ellipsoid „...” on the geographic 3D domain

It sets if elevations h is used or not in the calculations when converting from (φ, λ, h) → (X, Y, Z), from (X, Y, Z) → (φ, λ, h) and for projections which are dependent on the elevation. If h is not used in the calculation, it is considered that h=0.000 the geographic 2D case.

Map projection on the ellipsoid ...

This option becomes available only if the conversion type is (φ, λ) → (N, E) or (N, E) → (φ, λ).

Information on both the projections that can be selected and their parameters can be found at Description of the projection parameters.

Button View projection

Open the View Projection window. In this visualization window the graphical elements will be drawn in the selected projection according to the performed settings. The visualization window can be resized, the drawing can be enlarged or reduced using the buttons from the window and by rotating the wheel of the mouse. When moving the mouse cursor the values of the plane coordinates of the projection and geographic coordinates are shown in real time.

Note: Generally, the visualization of a projection is made for the entire globe but there are particular cases when the projection is visualized only on an area, the case of the projection with local application.