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1

It is entirely valid, but it may not produce the results you expect in any Cartesian coordinate space. So it isn't a problem with degrees or WGS84, but rather the mapping from the ellipsoid to a plane. If the polygon is very large, the mapping of the curved surface on the ellipsoid to the plane can produce some artifacts where a point looks like it would be ...


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Whenever you have to transform or convert data between two geographic coordinate reference systems (GeoCRS, also called datums), you may find that there are zero, one, or multiple possible transformations available. If there are multiple transformations, they usually differ by area of usage and/or accuracy. Some countries like Belgium have published ...


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QGIS is not designed to handle J2000 data. Your data would have 4 coordinates (X,Y,Z and time), while QGIS only handles 2-dimensional coordinates (long and lat or X and Y). It is possible to reproject coordinates with cs2cs if you set the prime meridian according to the time. Every hour from 12 UTC is a shift of 15° to the greenwich meridian: put 7 51 in a ...


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The EPSG registry lists two versions of CGCS2000: EPSG:4479 uses a 3-dimensional cartesian coordinate system based on the Earth's center EPSG:4480 uses Latitude, Longitude and ellipsoidal height. For the first one, see Help defining custom CRS in QGIS 2.2 how to use it in QGIS and the limitations of that CRS. For the second one, you can use the projection ...


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According to spatialreference.org, CGCS2000 should be +proj=longlat +ellps=GRS80 +no_defs The usual approach is to add this definition as a custom CRS if you cannot find it in the default CRS list of QGIS.


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I'd suggest not writing this yourself, but instead using one of the existing coordinate transform libraries, such as proj4j or the CRS part of GeoTools. From GeoTools (with some JTS help): import com.vividsolutions.jts.geom.Geometry; import org.geotools.geometry.jts.JTS; import org.geotools.referencing.CRS; import org.geotools.geojson.geom.GeometryJSON; ...


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I don't know the software you use, but I could get the data into QGIS: The corner points and the one from the second screenshot seem to be correct in North Kansas, and correspond to real estate borders in Google satellite imagery. Two sides are made up of streets that are in OSM maps as well. As you found out, the base point WGS84 coordinates are wrong ...


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Based on the steps you tried so far I think you have only created an on-the-fly version of what you want. Mosaic datasets do not change or create any new rasters, they just process them on the fly for fast visualization. If you export the resulting mosaic dataset as a new raster you should get the result you want.



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