2

I recently had a problem in QGIS which is - i guess - related to gdal and the identification of WKT definitions in the prj files. The problem is that the CRS ETRS89 / UTM zone 32N in Shapefiles coming from ArcMap are automatically (without message in QGIS) identified as ETRS89 / ETRS-TM32 - which is wrong.

The definition of ETRS89 / ETRS-TM32 is:

+proj=utm +zone=32 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

And ETRS89 / UTM zone 32N is:

+proj=utm +zone=32 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

So it seems to be the same, also the OGC WKT definitions are - as far as i see it - the same. But the ESRI WKT is - of course - different:

ESRI:

PROJCS["ETRS_1989_UTM_Zone_32N",GEOGCS["GCS_ETRS_1989",DATUM["D_ETRS_1989",
SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],
UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],
PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],
PARAMETER["Central_Meridian",9.0],PARAMETER["Scale_Factor",0.9996],
PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]]

OGC WKT:

PROJCS["ETRS89 / UTM zone 32N",GEOGCS["ETRS89",
DATUM["European_Terrestrial_Reference_System_1989",
SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],
AUTHORITY["EPSG","6258"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],
UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],
AUTHORITY["EPSG","4258"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],
PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",0],
PARAMETER["central_meridian",9],PARAMETER["scale_factor",0.9996],
PARAMETER["false_easting",500000],PARAMETER["false_northing",0],
AUTHORITY["EPSG","25832"],AXIS["Easting",EAST],AXIS["Northing",NORTH]]

So, my questions:

  1. Is there any possibility to adjust the wrong identification via gdal, so that QGIS can identify and set the CRS correctly?

  2. Is there any difference between those CRS? And if not - why do they have two different EPSG codes?

  • As per the Tour there should be only one question asked per question. – PolyGeo Jan 14 '17 at 11:12
  • About 2), EPSG:25832 is using Easting-Northing axis order while EPSG:3044 is using Northing-Easting order. This has an effect if you save data as GML, or if you make requests to WMS or WFS services. – user30184 Jan 15 '17 at 16:33
  • Same problem here: gis.stackexchange.com/questions/224238/… – Albert Jan 25 '17 at 9:21
1

The projection parameters are the same for both codes

Important is the contents of the * prj file. If it contains only the parameters and not the EPSG code itself, QGIS will use the first suitable parameter entry.

1) You can write the EPSG-Code (25832) in the PRJ-File

PROJCS["ETRS1989_UTM_zone_32N",GEOGCS["GCS_ETRS_1989",DATUM["D_ETRS_1989",SPHEROID["GRS_1980",6378137,298.257222101]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",0],PARAMETER["central_meridian",9],PARAMETER["scale_factor",0.9996],PARAMETER["false_easting",500000],PARAMETER["false_northing",0],UNIT["Meter",1],AUTHORITY["EPSG",25832]]

2) I think there are all the same:

ETRS - TM32: EuroGeographics Identifier(This identifier is as used by the information source but has been superseded by the INSPIRE identifier.)
NO_ETRS89 / UTM: EuroGeographics Identifier     
ETRF89 / UTM zone 32N (N-E): EPSG alias     
DE_ETRS89 / UTM: EuroGeographics Identifier     
ETRS89 / UTM zone 32: Germany alternative identifier(This is the EPSG name for CRS code 25832)
ETRS89 / TM32: EPSG alias   
ETRS89-TM32: EU INSPIRE identifier
  • 1) I would like to have a solution where it is not necessary to edit the prj manually. The user usually doesn't recognise that a wrong projection is selected. And ESRI doesnt add the EPSG-Code - so it always ends up in the wrong CRS in QGIS. – aleho Jan 14 '17 at 12:57
  • 2) From where is the list of CRS? – aleho Jan 14 '17 at 12:57
  • I checked the names of 2) - its from epsg-registry. I saw in the details of 3044 and 25832, that the difference between both is the order of northing and easting. On epsg-registry it says: See ETRS89 / UTM zone 32N (CRS code 25832) for CRS with preferred east-north axis order. So - actually it should make a difference, shouldn't it? – aleho Jan 14 '17 at 13:11
  • >> that a wrong projection is selected: Not wrong, but the first suitable! Qgis can not know what you want. Qgis can not know what you want, because it is not written anywhere – Mike Jan 14 '17 at 13:20
  • Imho between 3044 and 25832 there are no different (for projection) – Mike Jan 14 '17 at 13:30

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