These maps are made in the same way as our Globe Views and Globe Maps. The globe surface was constructed from a USGS 1 km global elevation grid, reduced in size to represent an approximately 2 km grid. For their size, the maps are highly detailed, with vestiges of 1 km detail evidenced by coastline details and the presence of small islands. No map is an enlargement or reduction of any other, and the amount of topographic detail is approximately proportional to the size (pixels x pixels) of the map. Geographic North is vertically upwards through the centre of each map.

All maps are supplied as 24-bit/16 million colour files. For delivery purposes, each map has been compressed just once at a 100% .jpg quality setting. Like all our products, we recommend that on the first opening of the map, you save it to your computer in uncompressed (.bmp) or lossless (.tif, .png) format.

Because the maps are views of the surface of a sphere, map scale varies, and the maps cannot be used as cartographic tools. However, in the map descriptions, we specify the “locus” of each map, which is the latitude and longitude of the center of the view, and, borrowing a Google Earth technique, the “eye alt”, which is the distance of the viewpoint above the globe surface. If you need to know the distance between points on the map, you can set up the same view on Google Earth and use the Google Earth ruler tool (remember that our maps are square, and your Google Earth window is likely to be rectangular, so you will see more to the left and right in Google).

Click HERE to open the height legend for the maps, which is different from the Mercator Basemaps.

If you want to “fade” the maps to make your own mark-up more prominent, simply increase the brightness and reduce the contrast of the map:





	Original map colouration	Brightness increased 50%,
		contrast reduced 50%

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