This Laboratory exercise introduced to projecting GIS data to ArcGIS. Map projection deals with spatial data defined on the curved surface of the earth and transforms it to the two dimensional surface of a map by mathematical algorithm . This exercise has been completed using ArcGIS 9.2. All data needed for this exercise were provided by Geography 7 Laboratory database.
Conformal projection is known as a Projection which preserves the original shape of the area of interest but not the area or distance. For instance, when we use Mercator Map as a world map it does hold distortion when you look at the map.
The area of the world is presented as Equal-Area projection, but it consist distortions. For example meridian are equally spaced , but the parallels are not. It is particular mapping from a sphere to a disk. It finds application for statistical analysis and in various scientific disciplines, for plotting the orientations of lines in three-dimensional space.
From equidistant maps projections we can measure a true distances from center of the projection. Equidistant map do have flaws too and can be misleading.
Equidistant maps preserve the distances between certain points, but scale is not maintained correctly by any projection throughout an entire map.” Most Equidistant projections have one or more lines in which the length of the line on a map is the same length (at map scale) as the same line on the globe, regardless of whether it is a great or small circle, or straight or curved. Such distances are said to be true.”( ArcGIS, Help file)
Distance between Washington DC and Kabul measured in this laboratory are about 4836. 6 miles
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