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    Re: Scale a small area plotting sheet?
    From: Frank Reed
    Date: 2016 Mar 1, 14:23 -0800

    I wrote previously:
    " In latitudes outside the tropics, this implies a different plotting scale for roughly every degree of latitude (eventually approaching every 34' of latitude at very high latitudes). From roughly 10° to 22°, it's approximately every two degrees of latitude."

    Just for completeness, if you want to stay within 1% on the scaling factor, the acceptable latitude range in minutes of arc is 34/sin(Lat). Suppose you have a scaled plotting sheet for 12° latitude. For that latitude, the quantity 34/sin(Lat) is +/-163' or 2.7° so you can safely use that scaled plotting sheet anywhere from latitude 9.3° to 14.7°. Another case: if you have a scaled plotting sheet for 45° latitude, the acceptable latitude range is +/-48'. You can use the plotting sheet within 0.6° of the central latitude, but you really should use a different plotting sheet for 44 or 46°.

    Frank Reed

       
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