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    Re: My plotting board
    From: Bill B
    Date: 2015 May 08, 15:25 -0400

    On 5/6/2015 12:26 PM, Samuel L wrote:
    > Bill,
    > Mercator sheet? How would I make it? Can you give me an example?
    As Frank has not jumped in to address my queries, I'll build a straw man
    and let the gurus tear it apart. :-)
    By "bad habit" it is my guess he is referring to calling all conformal
    projections "Mercator projections" as they are only a subset. In other
    other words, all Mercator projections are conformal, but not all
    conformal projections are Mercator.
    If you examine a true Mercator chart the distance between meridians are
    equal. It is the spacing between parallels that differ with latitude.
    With a UPS, the spacing between the parallels of latitude remain
    constant, and the meridians are spaced according to mean latitude. This
    is accomplished by using the outer scale on the UPS compass rose, or by
    using the longitude scale on the lower right. Perhaps conformal, but not
    My suggestion was to construct a true Mercator projection for your area.
    If you are still interested in the method, please contact me off list at
    billyrem42x9240zearthlink.net, substituting the AT symbol for "x9240z"

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