Bing Maps uses a slight variation of the Mercator projection. This is a conformal projection that is ideal for navigation, because shapes, directions, and angles on a map are constant. However, distance and scale distortion increases further away from the Equator. As a result, North-South lengths stretch in Northern Latitudes, such as in Finland, and in Southern Latitudes, such as in New Zealand. This is also why some areas, such as Greenland and Antarctica, appear huge on the map.
If you are experiencing inaccurate distance or line length calculations, because you are working in a location that is closer to the North or South pole and further away from the Equator, then use a spherical distance calculation.
To set the type of distance and area calculation to use:
- On the PRO tab, click Options, and Map Window.
- In the Map Preferences dialog box, select the Projection tab.
- In the Distance/Area using pane, either of the following:
- Spherical - The Spherical calculations measure distance according to the curved surface of the Earth. Spherical is the default. The data is first converted to Latitude/Longitude and then a calculation is produced. Lat/Long data will always use spherical calculations.
- Cartesian - The Cartesian method performs calculations on data projected onto a flat plane. Cartesian coordinates (x,y) define the position of a point in two-dimensional space by its perpendicular projection onto two axes which are at right angles to each other. Long/Lat projections cannot use Cartesian calculations.
- Click OK to save your setting.
For more information about map preferences, see Setting your Map Window Preferences.