4

Working with some data in the North Sea and basically I'm a bit fed up of working at a slant of 43.22 degrees. I was thinking it must be possible to define an orthogonal local coordinate system as a .prj file for my area. However I have no idea how to do this...

The desired centre of such a grid would be at 2°0'0"E 55°0'0"N and rotated by -43.22 or +46.78 so that the boxes in the image below go from rotated to orthogonal.

enter image description here


I managed to solve this myself by defining a .prj using a tutorial found at:

https://geonet.esri.com/thread/11068

For anyone to check, I used the bottom left corner as my origin and set the rotation to -43.22/136.78 and ended up with:

PROJECTION["Local"], PARAMETER["False_Easting",0.0], PARAMETER["False_Northing",0.0], PARAMETER["Scale_Factor",1.0], PARAMETER["Azimuth",-43.22], PARAMETER["Longitude_Of_Center",1.42624], PARAMETER["Latitude_Of_Center",55.102476],UNIT["Meter",1.0]]

  • 2
    I think you should cut/paste the answer in your question to become an answer. – PolyGeo Jun 7 '16 at 21:51
1

Alternatively to your solution (which seems to work in ARCGIS), you can set up an oblique mercaor projection. This would work in QGIS and GDAL-based software as well:

PROJ.4 :

+proj=omerc +lat_0=55.102476 +lonc=1.42624 +alpha=-43.22 +k=0 +x_0=0 +y_0=0 +gamma=0 +datum=WGS84 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

OGC WKT :

PROJCS["unnamed",
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        TOWGS84[0,0,0,0,0,0,0],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0,
        AUTHORITY["EPSG","8901"]],
    UNIT["degree",0.0174532925199433,
        AUTHORITY["EPSG","9122"]],
    AUTHORITY["EPSG","4326"]],
PROJECTION["Hotine_Oblique_Mercator_Azimuth_Center"],
PARAMETER["latitude_of_center",55.102476],
PARAMETER["longitude_of_center",1.42624],
PARAMETER["azimuth",-43.22],
PARAMETER["rectified_grid_angle",0],
PARAMETER["scale_factor",0],
PARAMETER["false_easting",0],
PARAMETER["false_northing",0],
UNIT["Meter",1]]

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.