Kavrayskiy VII projection

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Kavrayskiy VII projection of the Earth Kavraiskiy VII projection SW.jpg
Kavrayskiy VII projection of the Earth
The Kavrayskiy VII projection with Tissot's indicatrix of deformation Kavrayskiy VII with Tissot's Indicatrices of Distortion.svg
The Kavrayskiy VII projection with Tissot's indicatrix of deformation

The Kavrayskiy VII projection is a map projection invented by Soviet cartographer Vladimir V. Kavrayskiy in 1939 [1] for use as a general-purpose pseudocylindrical projection. Like the Robinson projection, it is a compromise intended to produce good-quality maps with low distortion overall. It scores well in that respect compared to other popular projections, such as the Winkel tripel, [2] [3] despite straight, evenly spaced parallels and a simple formulation. Regardless, it has not been widely used outside the former Soviet Union.[ citation needed ]

Contents

The projection is defined as

where λ is the longitude, and φ is the latitude in radians.

See also

Related Research Articles

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Bottomley projection

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Tissots indicatrix

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Hammer projection map projection

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Cassini projection map projection

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Wagner VI projection

Wagner VI is a pseudocylindrical whole Earth map projection. Like the Robinson projection, it is a compromise projection, not having any special attributes other than a pleasing, low distortion appearance. Wagner VI is equivalent to the Kavrayskiy VII horizontally elongated by a factor of ​. This elongation results in proper preservation of shapes near the equator but slightly more distortion overall. The aspect ratio of this projection is 2:1, as formed by the ratio of the equator to the central meridian. This matches the ratio of Earth’s equator to any meridian.

Cylindrical equal-area projection

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Natural Earth projection map projection

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Boggs eumorphic projection

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Nicolosi globular projection

The Nicolosi globular projection is a map projection invented about the year 1,000 by the Iranian polymath al-Biruni. As a circular representation of a hemisphere, it is called globular because it evokes a globe. It can only display one hemisphere at a time and so normally appears as a "double hemispheric" presentation in world maps. The projection came into use in the Western world starting in 1660, reaching its most common use in the 19th century. As a "compromise" projection, it preserves no particular properties, instead giving a balance of distortions.

Strebe 1995 projection

The Strebe 1995 projection, Strebe projection, Strebe lenticular equal-area projection, or Strebe equal-area polyconic projection is an equal-area map projection presented by Daniel "daan" Strebe in 1994. Strebe designed the projection to keep all areas proportionally correct in size; to push as much of the inevitable distortion as feasible away from the continental masses and into the Pacific Ocean; to keep a familiar equatorial orientation; and to do all this without slicing up the map.

References

  1. Snyder, John P. (1993). Flattening the Earth: Two Thousand Years of Map Projections. Chicago: University of Chicago Press. p. 202. ISBN   0-226-76747-7 . Retrieved 2014-11-05.
  2. Goldberg, David M.; Gott III, J. Richard (2007). "Flexion and Skewness in Map Projections of the Earth" (PDF). Cartographica. 42 (4): 297–318. arXiv: astro-ph/0608501 . doi:10.3138/carto.42.4.297 . Retrieved 2014-11-05.
  3. Capek, Richard (2001). "Which is the best projection for the world map?". Proceedings of the 20th International Cartographic Conference. Beijing, China. 5: 3084–93. Retrieved 2014-11-05.