About the Orthographic Maps
An orthographic map is a “view from space” map. We make our orthographic maps by draping a very
large 2D world map around a digital sphere in 3D modelling software to create a 3D globe. The globe is then
rotated so that the centre of the view is at the desired latitude and longitude, and the software "camera"
moved towards or away from the globe until the required map boundaries are obtained.
This procedure is an efficient way of making maps. However, it does not result in a true orthographic
projection. We justify our use of the term on the grounds that, for raster maps of the size we produce, it results
in maps that are indistinguishable from true orthographic maps.
More details.
We supply a free georeferencing and navigation aid in the form of a “graticule image” for each map.
The image is a 10 degree latitude-longitude grid of exactly the same size and orientation as the parent map. The centre
of each graticule image is marked and labelled, so you can assign the correct latitude/longitude values to each line
of the grid. The graticule file is a small greyscale .png file accessed by a link in the map description.
On the maps, geographic north is always vertically up through the centre of the map.
An orthographic projection is arguably the most natural map projection. However, because the map scale varies
along both axes, it is most useful if it is centered on your area of interest. If you like the orthographic
concept, but need a map centered on a specific location, please consider our custom map service.
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