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- Difference between projection and datum? 11 answers
Are the datum and the ellipsoid the same? What is a Datum?
The Earth is shaped like a flattened sphere. This shape is called an ellipsoid. A datum is a model of the earth that is used in mapping. The datum consists of a series of numbers that define the shape and size of the ellipsoid and it's orientation in space. A datum is chosen to give the best possible fit to the true shape of the Earth. in this article....