Mercator projection that shrinks toward pole

Question

I've noticed that lots of map viewer (especially those nautical chart viewer) will shrink a mercator projected chart while panning towards poles.

Is this some compensation for mercator distortion?

Is this a dedicated projection?

How to implement that?

you shouldn't crosspost in all possible sites/mailing list's... it is not a correct approach: 1 & 2
Formulas for the scale of a Mercator projection are given in the answer at gis.stackexchange.com/a/40659. Concerning your last question, what platform do you intend to use for the implementation?
I'm thinking that the shrink is to make the scale always the same along latitude, so , say (px, py) is normally projected coordinate, to get it shrinked, use (x, y) = (px*cos(lat), py*cos(lat))
If the Mercator implementation supports a standard parallel, they may be changing it to match the screen's central latitude. That will "shrink" a Mercator-based map.

Brad Nesom · Answer 1 · 2013-02-04 16:19:38Z

up vote 1 down vote

Here is a little puzzle that will illustrate what google mercator does.
Mercator puzzle

answered Feb 4 at 16:19

Brad Nesom
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1 Answer