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Is it somehow possible in QGIS to define a custom CRS which is based on UTM but accepts Easting coordinates that include the zone number?

The point behind this is, that I've got DXF files that I would like to include in my project. All of those are defined with complete coordinates.

When I select the UTM system with the zone, they plot way too far to the East because of the zone number.

One example point in them is

3243xxxx.371,551xxxx.924

I've found this topic on the same problem Importing UTM coords into QGIS: Handle UTM Zone

Someone mentioned EPSG:5650 there but for me that is not the correct one...

Since the DXF data is not points only I don't really know how to convert them to use a notation without the zone number...

  • Haha, welcome to Germany! We usually use AutoCAD to manually move all features of interest 32 million meters to the west. – Erik Mar 29 at 8:24
  • :) Unfortunately I'm not very familiar with CAD programs and I've only got access to the free version of Draftsight. I don't really know how I can move a complete drawing or even only some features by a fixed amount there :/ But I guess I have to figure it out somehow if it is not possible in GIS ;) – Steineklopfer Mar 29 at 8:39
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    Haha no worries, I figured it out. It was way easier than I imagined :) I just selected everything and used the MOVE command to move from 32000000,0 to 0,0. Thanks for the tip ;) Nevertheless it would be interesting if the original question is possible in QGIS as well :) – Steineklopfer Mar 29 at 8:45
  • In QGIS the equivalent tool is called Translate, you can find it in the Processing Toolbox. If that works for you, please consider writing up an answer to your question that includes both methods. I think it would be useful to others with the same issue. – csk Mar 29 at 16:04
  • Welcome to GIS.StackExchange!, @steineklopfer. You can add 33 million meters in the definition of the false east, in the creation of the personalized reference system. Or maybe I'm not understanding your question well, if you could edit it to include: What is the corresponding UTM zone? What is the coordinate that the point should have, in which CRS? What is the coordinate that you currently have, or how much is the difference between both coordinates? – Gabriel De Luca Mar 30 at 14:56
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For your needs there are these CRS defined in the EPSG database:

EPSG:5649
ETRS89 / UTM zone 31N (zE-N)
+proj=tmerc +lat_0=0 +lon_0=3 +k=0.9996 +x_0=31500000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

EPSG:4647
ETRS89 / UTM zone N32
+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=32500000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

EPSG:5650
ETRS89 / UTM zone 33N (zE-N)
+proj=tmerc +lat_0=0 +lon_0=15 +k=0.9996 +x_0=33500000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

EPSG:5651
ETRS89 / UTM zone 31N (N-zE)
+proj=tmerc +lat_0=0 +lon_0=3 +k=0.9996 +x_0=31500000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

EPSG:5652
ETRS89 / UTM zone 32N (N-zE)
+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=32500000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

EPSG:5653
ETRS89 / UTM zone 33N (N-zE)
+proj=tmerc +lat_0=0 +lon_0=15 +k=0.9996 +x_0=33500000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

The definitions differ in the axis order and zone number.

See also http://mobile.adv-online.de/AdV-Produkte/binarywriterservlet?imgUid=93730140-3898-e931-6b1e-502172e13d63&uBasVariant=11111111-1111-1111-1111-111111111111 and Which UTM zone 32N with prefix should I use in Rhineland-Palatinate (Germany)?

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What we basically want to achieve is to import UTM coordinates that include the zone number.

3243xxxx.371,551xxxx.924

and turn them into UTM coordinates without a zone number, because the CRSs in QGIS already add that.

43xxxx.371,551xxxx.924

The second one will plot correctly with UTM zone 32N selected. The first one will plot 32000000 meters too far to the East. Unfortunately most DXF files I've come across do use that full format.

What I would have loved to see is a CRS definition which automatically takes the zone number from the coordinates. But I guess that is not possible.

What might be possible, but I haven't tried that, is what Gabriel suggested. Add the "zone" as false Easting. However, that would have to be done for each zone individually again.

Now here are two work arounds for this problem.

What I settled for atm is to move the features with "Translate" like csk suggested. It is part of the toolbox under vector geometry.

Be sure to select the correct UTM CRS before you do that. Otherwise it won't translate correctly because the input might be in degrees instead of meters.

For my example I then need to translate the layer in question by -32000000 meters in x direction. Because it is part of UTM zone 32. If you'd have complete coordinates from zone 33 then you'd have to translate it by -33000000 meters. Basically getting rid of the first two digits of the X coordinate.

Afterwards it will plot in the correct location.

The same thing can also be accomplished in the CAD software, before the export, with the "MOVE" command. In Draftsight select everything you need and just enter MOVE in the command line. Followed by the start coordinate 32000000,0 and the target coordinate 0,0 (for zone 32). After the export it won't have the zone number included in the X coordinates because of the artificial move.

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