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Transverse Cylindrical Projections

A Transverse Cylinder (Transverse Mercator) can be used to produce a cylindrical image from the globe. Wrap the cylinder around the earth with the film touching it at the equator. The open ends of the cylinder are oriented toward the north and south poles.

Since the Earth is nearly a sphere, there are other ways in which our photographic cylinder can be wrapped around the Earth. We can rotate our cylinder 90 degrees so that the open ends are to the left and right and expose the film.

The crisp clean lines still represent the regions where the photographic film was close to the Earth. Instead of an east/west direction, the crisp clean lines follow a great circle of longitude in a north/south direction. There is little distortion as we proceed north and south close to the center, while distortion increases as we move to the east and to the west. This projection is known as the Transverse Mercator projection.