NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Mercator vs. Great Circle Charts
From: Carolyn Seefer
Date: 2001 Aug 29, 10:24 AM
From: Carolyn Seefer
Date: 2001 Aug 29, 10:24 AM
In a message dated 8/29/2001 9:05:39 AM Pacific Daylight Time, navsys@PINEFIELDS.COM writes: > The question is unclear to me. What is meant by "true direction"? Is > this the course to be steered or just a bearing? My guess is that "true direction" in this case means if one can gauge N-S-E-W just by looking at the chart. When I look at the Mercator chart, it seems as though I can tell directions accurately, and all compass roses on the chart are identical. With the great circle chart, on the other hand, the distortion seems to also distort the actual directions. Just by looking at the chart, I can't actually determine what is "true North." It seems that adjustments would have to be made. Again, I'm new to all of this! By the way, thanks for pointing me to the NIMA publications online. I've already started reading Chapter 3 of the Bowditch text. This is very helpful; Bowditch hasn't been mentioned in class yet. Carolyn Seefer
