Gall Projection

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A cylindrical projection that is equal-area. Very similar to the Cylindrical Equal Area projection (also known as the Lambert Cylindrical Equal Area projection) but with standard parallels at 45 degrees North and South.

 

Scale

 

No distortion of scale and shape at the standard parallels of the normal aspect but great distortion of shape and scale otherwise.

 

Distortion

 

Substantial shape and scale distortion near points 90 degrees from central line resulting in vertical exaggeration of Equatorial regions with compression of regions in middle latitudes and extreme vertical aspect compression in higher latitudes. Greater vertical aspect (taller) than the Cylindrical Equal Area projection upon which it is based.

 

Usage

 

Rarely used in professional cartography due to shape distortion. Usable for practical purposes only near the Equator.

 

Origin

 

Devised by James Gall in 1855 as a modification of the 1772 projection by Johann Heinrich Lambert.

 

The Gall projection was adopted by Arno Peters of Germany in 1967, who claimed the invention of the projection as his own, despite the well-known invention of the projection by Gall in 1855. The "Peters projection" is, in fact, identical to the Gall except for an insignificant difference in standard parallels.