Deryk,
The Fahud Datum of 1954 (PSD93) uses the Clarke 1880 as its ellipsoid of
reference. The Oman Transverse Mercator projection has a central meridian
of 54ºE of Greenwich, a scale factor at origin of 0.9997, and a False
Easting of 500km. The origin point of the Fahud 1954 is near station
"68-024" where the latitude of origin is 22º 17' 31.182" N, and the
longitude of origin is 56º 29' 18.820" E, and H = 323.50 meters as
determined by trig leveling from Muscat local mean sea level. The original
origin point at F.N.Fort (station "F1" with defining azimuth to station
"F2" has been destroyed).
In October of 2005, Wilfred of Medco Energy posted the 7-parameter
transformation from WGS84 to PSD93 on the MapInfo List as:
dX = +180.624m
dY = +225.516m
dZ = -173.919m
dS = -16.71006ppm
Rx = -0.80970"
Ry = -1.89755"
Rz = +8.33604".
Test Point:
PSHD93
20º 20' 56.967"N
56º 31' 15.467"E
2,250,000.00
450,000.00
0.00m
PSD93 (Clarke 1880)
20º 20' 56.967"N
56º 31' 15.467"E
2,250,000.00m
450,000.00m
-2.063m
WGS84
20º 20' 58.495"N
56º 31' 25.456"E
2,250,238.67m
450,290.96m
-34.797m
I have no idea where Wilfred obtained his parameters or his data set, but
it WAS posted on the Map Info List.
If you do find other "better" information, please do the List the courtesy
of posting new and "better" information, observations, and parameter data.
Good Luck,
Clifford J. Mugnier, C.P., C.M.S.
Assistant National Director (current),
National Director (2006-2008)
Photogrammetric Applications Division
American Society for Photogrammetry and Remote Sensing
and
Chief of Geodesy,
CENTER FOR GEOINFORMATICS
Department of Civil Engineering
CEBA 3223A
LOUISIANA STATE UNIVERSITY
Baton Rouge, LA 70803
Voice and Facsimile: (225) 578-8536 [Academic]
Voice and Facsimile: (225) 578-4474 [Research]
======================================================
http://www.asprs.org/resources/GRIDS/
http://www.cee.lsu.edu/facultyStaff/mugnier/index.html
======================================================
> Does anyone have a datum/translation file for Mapinfo.prj for the OMAN
NATIONAL GRID. Mapinfo.prj has the Lat Long string only. Thanks
Regards
Deryk Forster
Senior Geologist
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