What is the scale factor for a Mercator projection?
From wikipedia’s Mercator projection: scale factor = secant (latitude) = 1 / cosine (latitude) Generally, divide map distance by the scale factor to get globe distance. But what about “long” lines, at different latitudes, what scale factor to use?
How do you calculate the scale factor of a map?
You are absolutely correct. From wikipedia’s Mercator projection: scale factor = secant (latitude) = 1 / cosine (latitude) Generally, divide map distance by the scale factor to get globe distance. But what about “long” lines, at different latitudes, what scale factor to use? According to EF Burkholder, for.
What was the latitude of the Mercator 1569 map?
Mercator 1569 world map ( Nova et Aucta Orbis Terrae Descriptio ad Usum Navigantium Emendate Accommodata) showing latitudes 66°S to 80°N. The Mercator projection ( / mərˈkeɪtər /) is a cylindrical map projection presented by Flemish geographer and cartographer Gerardus Mercator in 1569.
Where does the scale factor in proj4 come from?
The scale factor is named in a variety of sources I read. This sources explained its definition and its value for some projections. In the source code of Proj4, for the mercator projection (sphere and ellipse case), the scale factor influences the coordinates on the projection :
How to convert Mercator formula to equirectangular formula?
To go from Mercator to Equirectangular, you need to first (reverse) project Mercator (NE) to Lat/Long, and then (forward) project Lat/Long to Equirectangular (NE). (2) Mercator and Equirectangular formula each has two forms – one for ellipsoid, and one for sphere.
How to convert a particular point on a Mercator map?
How do I convert a particular point on a Mercator map (points in a Mercator map svg) to WGS84 coordinates? Is it simply a direct translation of the x,y values, using a multiplier which matches the map width & height to -180..180 and -90..90? WGS84 is an ellipsoidal coordinate system.