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Redefining the original file as WGS84 does the trick at least for accuracy for any practical purpose. The following was sent by a customer care rep at ESRI... 1] ITRF 2008 is a datum definition that takes continental drift into consideration. 2] The WGS 1984 definition used in ArcGIS Desktop is the original definition, and has not been updated to take ...


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Different infos: some lines are not useful By default, these below projections already exist so you do not need to declare them Proj4js.defs["EPSG:4326"] = "+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs"; Proj4js.defs["EPSG:900913"]= "+title=GoogleMercator +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m ...


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Using gdal. Have a look at gdal_translate to convert to from tif to another format (although the tif is likely the best option). Then use gdalwarp to reproject to mercator. Gdal is written in python so you should be able to incorporate it straight into your workflow.


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Maybe Spacedman have already gave the answer but I was actually looking for formulae . I have found this page which is Turkish so I'll give you only the part you can understand. It says with this formulization we can transform our Geographic(Ellipsoidal) coordinates to Cartesian Coordinates. ( "h" is ellipsoidal height) Then I have found this page which is ...


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I'll use spherical coordinates as defined here on Wikipedia which uses phi and theta (which is probably your lambda). Phi is the angle from the north pole. Hence if the WGS84 point is 10.0.0N, phi will be 80 degrees. For a point in the southern hemisphere, say 12.30.00S, phi will be 90 + 12.5 = 102.5 degrees. Theta is just the longitude in degrees, if the ...


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0.0009° is 3.24 arc sec, which is 3.24 * cos(40°) * 101 ft/asec = 251 feet, where I’m assuming your latitude is ~40° (northern Nevada). This suggests that the transformation by the CoordTrans software is not including any datum shift of any kind. I don’t the know the details of how you are interfacing the Trimble to the CoordTrans software, but perhaps the ...


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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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