[Proj] Map Projection Amusements and Other Things
j.l.h.hartmann at uva.nl
Mon Aug 20 07:43:36 EDT 2007
Thanks Mr. Anderson. Very interesting and funny pictures, and also a
very useful site.
Dr. J. Hartmann
Department of Gepgraphy
University of Amsterdam
Paul B. Anderson wrote:
> - Hi Everyone,
> In regard to recent discussions on cylindrical map projections, I
> thought I would toss a 'tangent' thought into the mix.
> Years ago, due to being confused myself, I researched the available
> literature for cylindrical map projection formulas. I eventually gave
> the notes I made to Gerald Evenden and he greatly expanded on them.
> Chapter 4 of his Libproj4 Manual (Mar 2005), in my 'obviously biased'
> opinion, is the best reference one can find on cylindrical map
> projections. Enough said on that subject!
> BTW, daan Strebe I just recently came across your Oct 06 CaGIS Map
> Projection article. Thanks for mentioning me!
> I've recently recovered enough from medical problems to be able to
> resume, as a student, a 'GIS Certificate' course at ODU so that I could
> learn 'ArcGIS 9.2'. My new Instructor, for some reason, was not amused
> to learn that the textbook she chose for the class (ISBN: 0-13-129317-6)
> features some of my graphics on page 44. Regretfully, there are at least
> 4 author introduced errors on that page alone.
> Some graphics:
> On the MapHist list-serv in 2005 someone made a comment about a map
> based on the phrase 'The World is my Oyster'. I replied with the
> following comments. Note that my claim here is that the graphics below
> are merely visually interesting, however, for most of them the forward
> formulas are available.
> This one was where I was experimenting with summing the X and Y
> coordinates of different graticule groups just to see what developed:
> Everyone that experiments with map projection formulas comes up with
> unexpected, but visually interesting mistakes. Here are some more of my
> This one was where I was experimenting with the Nell Modified Conic --
> until I realized that Snyder's description (in Flattening) was
> incomplete. The pattern produced in what I had already done just popped
> out at me, so, I cleaned the graphic up (lots of grunt work) in Corel
> Draw and saved it:
> Dr. Don Zeigler (Geog Dept, ODU) named this one the Bay Window
> projection. It was one of my earliest goofs. Even though I saved the
> formulas, I don't remember how I arrived at this one:
> This one came about because I accidentally put the divide symbol in the
> place of the subtract symbol in the X coordinate portion of Moir's
> formulas. At that time I had not seen an actual graphic of the
> projection and John Snyder was the one who caught my error. He suggested
> I save the formulas and name it the 'Bad Times' projection:
> This Polycylindrical projection came about from experimenting with
> various Y coordinate formulas in place of the ones Dr. Tobler used in
> his paper on Polycylindricals. I kept it because it was 'visually'
> I did not give this one a name. It is amazing in that with one set of
> formulas the outer portion of the graticule forms a rectangle while the
> parallels within are curved:
> A link to Gerald Evenden's Libproj4 Manual that I mentioned above can be
> found at my web site.
> Thanks for reading.
> Paul B. Anderson FCCS (USN, Retired)
> Kingsport, TN native living in Norfolk, VA
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