Given a UTM easting (E), northing (N) and height (H), this app computes the grid/point scale factor, elevation/height factor and combined scale factor values.
The following formulas are used:
Grid scale factor (GSF) = k0 + (E-E0)^2 / (2 * r0^2)
Elevation factor (EF) = R / (R + H + N)
Combined scale factor = GSF * EF
k0 = Grid scale factor at central meridian (defaults to 0.9996)
E0 = False Easting (defaults to 500000)
r0 = Geometric mean radius of curvature scaled to the grid (defaults to 6375767.131)
R = Mean radius of earth (defaults to 6365314.378)
N = Height of ellipsoid above geoid (defaults to 0.0)
The defaults are chosen so that the results agree with the following document:
The defaults can be changed by selecting the menu and choosing "Settings".
Point scale factor
This app has access to :