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3

I suggest (as Vince) to put the center of your custom projection in the middle of the study area at 168 W 59 N. The following projections might give best results: +proj=laea +lat_0=59 +lon_0=-168 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs +proj=aea +lat_1=53 +lat_2=65 +lat_0=59 +lon_0=-168 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs +proj=tmerc ...


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From QGIS you can select 'Save As' and specify the output coordinate system. Right click on the layer, select save as and change the coordinate system: It is important to set CRS to 'Selected CRS' and not to 'Project CRS'; in a previous post on the subject it was determined that there is a bug in using the project CRS. However, when you make the shape ...


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You've caught a lot of the differences. Esri never adopted the WKIDs for the map projection algorithms or parameter names so those are all different. We didn't agree with how carefully defined the parameter definitions are. Ours are more generalized. We don't support TOWGS84 nor some of the newer keywords. When we compare strings (names), we ignore the ...


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I don't have such a list, but going through the GDAL code will guide you: https://svn.osgeo.org/gdal/trunk/autotest/osr/osr_esri.py https://trac.osgeo.org/gdal/browser/trunk/gdal/ogr/ogr_srs_esri.cpp https://trac.osgeo.org/gdal/browser/trunk/gdal/ogr/ogr_srs_esri_names.h https://trac.osgeo.org/gdal/browser/trunk/gdal/ogr/ogrspatialreference.cpp


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As of Jan 2015, I'm not aware of any open source implementation that fully supports every possible option in geopackage. The spec is authoritative (but likely to be updated) for implementation, so if you want to (or really don't want to, but still have to) write your own map engine, work from that. Look for a sane subset/profile, rather than trying to do it ...


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The central meridian of the UTM systems is at 93°W +/- 6° and has a value of 500000m in the local system. So you have to look up those central meridians and see which aligns with your UTM grid. The next central meridian will be about 300 km away, and appear bended in the chosen UTM projection.


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There should be essentially no difference. I don't know quite how to clearly explain this, but when re-projecting, you are in fact re-sampling at the same time, even if your cellsize were to remain the same. In order to project, the projection algorithm has to know where to 'place' the data, i.e., it has to have a location to project each cell value to, ...


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You have to distinguish between project CRS and layer CRS. If you use Google/Bing background, the project CRS must be set to EPSG:3857. The other layers you add can have a different CRS. On-the-fly-reprojection will align these layers, even if they have a different projection than the background. What you should not do is to use Set CRS for Layer. This ...


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I'm going to put this as an answer, but I'm making several assumptions so this may not be the 'right' answer! This will prove whether or not the values are ED1950 UTM 33 North but with the leading digits stripped off. Delete any coordinate reference system from the problematic shapefile. A very easy way to do this is to delete (or rename) the .prj file. ...


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An old Shapefile projected in GK3 although with a Transverse Mercator as Projection System was found and deleted. After restarting the PC Computer, all Settings for GK3 are now consistent across the different zones.


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I can't figure out how this is occurring. I stepped back in time, and I can't find an occurrence where 31467 ever used Transverse Mercator for the projection name. It would be quite unusual because I usually copy and paste definitions when setting up a set of zones like this, so I would expect all zones to have Transverse Mercator. You're correct that at ...


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I am guessing your basemap is in Web Mercator? Handle the graphics and convert their geometry to Web Mercator individually arrayUtil.forEach(graphicsLayer.graphics, function(g){ var geom = esri.geometry.geographicToWebMercator(g.geom); g.setGeometry(geom); });


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Depending on which version you have, you can add translation/rotation/scale information to a CAD layer via its layer property page in ArcMap. There's an option to enable an extra transformation. Another possibility is to incorporate the LDP scale factor (LDPSF) into the existing coordinate reference system. If it's Transverse Mercator-based, multiply the ...


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As a reference, I took the file linked here: http://oceancolor.gsfc.nasa.gov/forum/oceancolor/topic_show.pl?tid=5426 gdalinfo on the subdataset 37 returns: geospatial_lat_max=24.78230858 geospatial_lat_min=5.343300343 geospatial_lon_max=139.3295746 geospatial_lon_min=126.3987579 ... Lower Left Latitude=24.78230858 Lower Left Longitude=134.9941864 Lower ...


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If you don't want to use an equal-area reprojection, you might get acceptable accuracy by calculating an approximation with the field calculator. It will calculate polygon areas as DecimalDegrees^2 with the $area field, but you would need to correct it for the decreasing scale of the longitudinal measurements. Entering an expression of: ...


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If you digitized the vector layer based on the raster but had a wrong CRS specified for the vector layer, the easiest option should be to simply overwrite the Shapefile's .prj file with the correct CRS information.


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Have you tried an affine transformation? Yours is a typical case for such kind of transformation for cartesian coordinates (i.e., not for lat-lon coordinates). Basically, you would need to pick at least 3 well spread common points on both your vector and raster layers (for example, a street intersection) and arrange their coordinates in a matrix like this: ...



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