My understanding is that EPSG:4326 specifies a projection,

with WGS84 as the Coordinate Reference System (the agreed abstract geometry of the earth)

and no coordinate transformation (really, the sphere of the earth is projected into 2D onto a cylinder)

That wikipedia Mercator map does appear to stop before the poles, couldn't say precisely at what latitude though.

----- Original Message ----

From: Immanuel Scholz <

[hidden email]>

To:

[hidden email]
Sent: Thursday, January 12, 2006 11:56:42 PM

Subject: [Openstreetmap] Formula for EPSG:4362 and questions to mercator projection?

Hi,

can someone explain me the formula for the projection "EPSG:4362" used in

WGS84?

It looks a bit like a mercator projection but with the pole not as much

distorted... ?

And when we are on it: The mercator projection can not project the north- and

south pole correctly. A picture of the whole world would be infinite in

height.

How comes, that there are maps of the whole world in mercator projection?

http://en.wikipedia.org/wiki/Image:Mercator-proj.jpegAre there a standard at which latitude the projection stops? If I stop at +-85

degree of latitude, I get a map with roughly equal dimension in width and

height. Is the "border latitude" for mercator somewhere there?

Or is some kind of magic used to project the near-pole regions in mercator

projection and the formular at

http://en.wikipedia.org/wiki/Mercator_projection is simple wrong?

Ciao, Imi.

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