CD-Sextant - Build your own sextant - Pole Shift Survival Information

Navigator Light Software
Rhumb lines (RL) are routes with constant true course. They are represented by straight lines in Mercator charts and curves
in Gnomonic charts (the opposite of LGCs). RLs are easy to navigate because the course is constant. They are, however, a
little longer (the difference is larger in higher latitudes).
Navigator Leg Calculator will calculate both LGC and
RL routes between the two end points. To open the Leg
Calculator, press the calculator button in the toolbar or
choose 'Routes, Leg Calculator' in the menu.
Besides distance and course, Navigator shows the
difference between the two options and builds routes with
specified number of segments.
These routes can be inserted in the current desktop.
Routes are added to the desktop with names "Rhumb
Line" and "Great Circle". You may change these names in
the route editor.
In the picture to the left, the yellow line is the RL route
and the red one is the LCG (both created with 22 points).
The difference between the two is 41.8 NM (1.26%). The
LGC route has a crosstrack difference of 241 NM to the
RL route (that is, it goes up to 4° south of the RL).
When building the routes, LGC route points are set by the
program at constant longitude increments. RL route points
are set at constant distance increments.
Chapter 4- ChartMaker program
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The ChartMaker program was designed to work with chart images in formats GIF, JPG and BMP, and prepare them for
use in the Navigator chart viewer.
This program has two main functions:
1. Importing a raster chart images, producing CID files.
2. Making vector charts (i.e. digitalizing points and polygons), producing CHT files.
How it works
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A computer image is formed by a large number colored dots - also known as pixels - disposed in a rectangular mesh. If the
image is from a nautical chart or satellite photo, an algorithm can be designed to find the real world coordinates of any of
these pixels and vice-versa. This is exactly how ChartMaker works.
The first step to make a vector chart or to import a raster chart image is to establish the scale model between the image and
the real world. To do this, you have to click 3 reference points and enter their world coordinates (Lat/Lon pair). This is
enough to define a scale between the real world and the image pixels.
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