# Transverse Mercator (South Oriented)

Name | Transverse Mercator (South Oriented)
EPSG Code | 9808
GeoTIFF Code | CT_TransvMercator_SouthOriented (27)
OGC WKT Name | Transverse_Mercator_South_Orientated
Supported By | EPSG, GeoTIFF, OGC WKT

### Projection Parameters

Name | EPSG # | GeoTIFF ID | OGC WKT | Units | Notes
--- | --- | --- | --- | --- | ---
Latitude of natural origin | 1 | NatOriginLat | latitude_of_origin | Angular |
Longitude of natural origin | 2 | NatOriginLong | central_meridian | Angular |
Scale factor at natural origin | 5 | ScaleAtNatOrigin | scale_factor | Unitless |
False Easting | 6 | FalseEasting | false_easting | Linear |
False Northing | 7 | FalseNorthing | false_northing | Linear |

### EPSG Notes

For the mapping of southern Africa a south oriented Transverse Mercator projection is used. Here the coordinate axes are called Westings and Southings and increment to the West and South from the origin respectively. The Transverse Mercator formulas need to be modified to cope with this arrangement with

    	Westing, W = k0 *[A + (1 - T + C)A3/6 + (5 - 18T + T2 + 72C - 58e'2)A5/120] -
    FE

    	Southing, S = k0{M - M0 + *tan*[A2/2 + (5 - T + 9C + 4C2)A4/24 +
    				(61 - 58T + T2 + 600C - 330e'2)A6/720]}- FN

In these formulas the terms FE and FN have been retained for consistency of the terminology. For the reverse formulas, those for the standard Transverse Mercator above apply, with the exception that:

    	M1 = M0 + (S + FN)/k0
    and	D = (W + FE)/(*1k0), with *1 = * for *1