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I want to have a custom Mollweide Projection (from ESPG: 53009) in QGis, that has it's center points somwhere else than 0,0 degrees. Let's say at -10,-60 degrees.

Here is the wkt for the epsg:53009 one:

PROJCRS["Sphere_Mollweide",
    BASEGEOGCRS["Unknown datum based upon the Authalic Sphere",
        DATUM["Not specified (based on Authalic Sphere)",
            ELLIPSOID["Sphere",6371000,0,
                LENGTHUNIT["metre",1]]],
        PRIMEM["Greenwich",0,
            ANGLEUNIT["Degree",0.0174532925199433]]],
    CONVERSION["Sphere_Mollweide",
        METHOD["Mollweide"],
        PARAMETER["Longitude of natural origin",0,
            ANGLEUNIT["Degree",0.0174532925199433],
            ID["EPSG",8802]],
        PARAMETER["False easting",0,
            LENGTHUNIT["metre",1],
            ID["EPSG",8806]],
        PARAMETER["False northing",0,
            LENGTHUNIT["metre",1],
            ID["EPSG",8807]]],
    CS[Cartesian,2],
        AXIS["(E)",east,
            ORDER[1],
            LENGTHUNIT["metre",1]],
        AXIS["(N)",north,
            ORDER[2],
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["unknown"],
        AREA["World"],
        BBOX[-90,-180,90,180]],
    ID["ESRI",53009]]

Which parameters do I tweak and how?

I guess it must be the PRIMEM or the Longitude of natural origin but I don't know where to change the latitude.

Just changing the natural origin parameter to -60resulted in this: enter image description here

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  • 2
    Not the PRIMEN but the Longitude of natural origin parameter. But the projection is not oblique so you can't change the latitude of the center. If you really need to make such a map you should rotate the original data (as if you rotated the continents, leaving for example Antarctica outside the south pole) the angle you want, and then apply the projection. Commented Oct 21, 2022 at 2:44
  • Related unanswered gis.stackexchange.com/questions/289428/…
    – Hans Erren
    Commented Oct 23, 2022 at 15:23
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    Here an answer about "rotate the world instead of the projection": gis.stackexchange.com/a/414669/133276. The dateline issues are another problem. It is related in the way polygon geometries are stored and rendered. I only found a handmade workaround in this question: gis.stackexchange.com/q/347157/133276. Commented Oct 26, 2022 at 7:52

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