Geocart menu class: Pseudocylindric
Geocart family: Putniṇš
Equally spaced parallels
Neither conformal nor equal area
Meridians: Central meridian is a straight line half as long as the Equator. Other meridians are equally spaced portions of hyperbolas, concave toward the central meridian.
Parallels: Equally spaced straight parallel lines, perpendicular to the central meridian.
Symmetry: About the central meridian or the Equator
True along latitudes 21°14' N. and S. Constant along any given latitude; same for the latitude of opposite sign. Constant along the central meridian.
Similar to other pointed-polar pseudocylindricals but not free of distortion at any point.
Presented by Reinholds V. Putnins of Latvia in 1934
Putnins P6 equal-area projection (1934) has hyperbolic meridians identical in shape to those of the pointed-polar P2; parallels are straight but are spaced for equal area. Putnins P2' projection (1934) has hyperbolic meridians, but the poles are straight lines half the length of the Equator. Parallels are equally spaced. The projection is not equal area. Putnins P6' equal-area projection (1934) has hyperbolic meridians identical in shape to those of the flat-polar P2', but parallels are straight lines spaced for equal area.
Description adapted from J.P. Snyder and P.M. Voxland, An Album of Map Projections, U.S. Geological Survey Professional Paper 1453. United States Government Printing Office: 1989.