How to specify projection for export of shapefile?

Shape file .prj file after export have no "PROJCS" specified. 

As far exported prj file is following:  

No matter, if I'll change projection (from Geographical to OSGB) of the layer in the project, result is always the same.

In attachment there is the file that have "PROJCS" in the projection file, I wish to get the same with GM. 

This is .prj content from attachment: 
PROJCS["OSGB_1936_British_National_Grid",GEOGCS["GCS_OSGB 1936",DATUM["D_OSGB_1936",SPHEROID["Airy_1830",6377563.396,299.3249646]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",49],PARAMETER["central_meridian",-2],PARAMETER["scale_factor",0.9996012717],PARAMETER["false_easting",400000],PARAMETER["false_northing",-100000],UNIT["Meter",1]]
As the input I'm using DWG file.

Best Answer

  • bmg_bobbmg_bob Global Mapper Programmer Posts: 1,971
    Answer ✓

    After you load your shapefile, change the projection to OSGB using the Configuration dialog (Projection tab), not the layer options dialog.  Afterwards, when you export the shapefile, be sure to check the option to write a PRJ file also.



  • linnylinny Posts: 3
    I'm very amatuer , but do you need the prj file? The times I've exported shapefiles I get better results not using the prj file
  • MiroslawaMiroslawa Posts: 23

    Thank you for that. Now .PRJ file contain PROJCS information, and can be open by the website, which I had to use.

    It was tricky to find it though. So for the future that can be found in Tools -> Configure -> Projection

    Some programs require right projection file to get good positioning, so it's not my choice use it or not.

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