Mapping plane scale factor – Spectra Precision Survey Pro v4.6 Ranger User Manual User Manual

Page 117

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107

Mapping Plane Scale
Factor

When converting distances on a map to distances on the ground, you

must correct for two different scale distortions. First, the effects of the

map projection distortion must be corrected with the mapping plane
scale factor. Second, the geometric effect of your height above the

reference surface (ellipsoid height) must be corrected with the

ellipsoid scale factor. Generally, these two scale factors are multiplied
together into the combined scale factor. Although the scale factor is

computed with differential equations of the map projection, one can

visualize it in a geometric sense. Consider the following diagrams:

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