NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Portuguese shipwreck question
From: Frank Reed
Date: 2009 Nov 2, 18:25 -0800
From: Frank Reed
Date: 2009 Nov 2, 18:25 -0800
John, you wrote: " The scatter plots were my first crude attempts to see if I could figure out what these places corresponded to. I didn't get as far as actually putting onto a Mercator projection, however. If you know of some software were one can input these points onto a Mercator projection, that would be nice." Whoa there. WHY in the world would you want these positions plotted on a Mercator projection?? The "scatter plot" you've made is just fine. All you need is a base map on the same projection. Technically, a one-to-one lat/lon projection is called "equirectangular" or "plate carre". There's a nice Wikipedia summary here: http://en.wikipedia.org/wiki/Equirectangular_projection What you need is a base map on the same projection. There are plenty of these on the Internet. If you want a "better looking" projection for Europe and the Near East/Middle East, you may want to look at a conic projection. But if it's just for placing points in the right places on the map, there is no reason to go beyond the equirectangular projection. I make maps of world history for a living in case you haven't followed up the URL in my email address. See the "Centennia Historical Atlas" at www.HistoricalAtlas.com. That's me. The projection in my atlas is conic. -FER --~--~---------~--~----~------------~-------~--~----~ NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList+@fer3.com -~----------~----~----~----~------~----~------~--~---
