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Equirectangular Earth | by hangglide
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Equirectangular Earth

This is an equirectangular projection of composite satellite images from NASA. While it is clearly not my photo, I have included it here to demonstrate the interactive equirectangular projection tool on a familliar image (earth).

 

Aldo made a similar version that is flipped. That way when it is viewed interactivly it is as if you are on the inside of the earth looking out.

 

Here is the description of the equirectangular projection taken from www.wikipedia.com:

 

The plate carrée projection or geographic projection or equirectangular projection, is a very simple map projection that has been in use since the earliest days of spherical cartography. The name is from the French for "flat and square". It is a special case of the equidistant cylindrical projection in which the horizontal coordinate is the longitude and the vertical coordinate is the latitude.

 

The spherical earth can only be mapped onto a developable surface by allowing distortion, so certain geometric properties on the sphere are not preserved. The Plate Carrée projection is a cylindrical projection but unlike the Mercator projection, the entire sphere, including the poles can be represented on a finite sized map. The projection is not a conformal map so angles are not preserved.

Because of the distortions introduced by this projection, it has little use in navigation or cadastral mapping and finds its main use in thematic mapping. It has also become a de-facto standard for computer applications that process global maps, such as Celestia, because a given co-ordinate is very easily identifiable in an image file.

 

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Taken on July 29, 2004