1

I would like to convert a shapefile which has +ellps=bessel to +ellps=WGS. In my understanding, even QGIS 1.8.0, it is impossible.

Let me know the free software which is able to convert shapefile from bessel to WGS.

5

It is very simple: Load the shapefile into QGIS, right-click on the Layer -> properties , general tab should contain EPSG:4004 (or an EPSG code of some other CRS that is based on the bessel ellipsoid).

Then right-click again, Save As..

Format: ESRI Shapefile
add a different file name
CRS -> Select, EPSG:4326 
  • Thank you for your answer. I tried your recommend way. But,,,it does not work in QGIS with different ellipsoids. Thanks!! – Jermain Marthin Jan 11 '13 at 8:28
  • 2
    It definitely will. If your shapefile is in EPSG:31276, this number should show up in layer properties. With SaveAs EPSG:4326, you get data in WGS84 lat/lon degrees. If you want results in metres again, you should choose a UTM CRS, EPSG:32633 or following. If you want to align to Openlayers plugin with Google or OSM, choose EPSG:3857. But this is not necessary, with on-the-fly-projection on it can remain EPSG:4326. – AndreJ Jan 11 '13 at 15:23
3

QGIS can do that transformation but, to convert data which have coordinate systems with different ellipsoids, you have to have transformation parameters (+towgs for example) or know exact EPSG code of both data sources. Knowing only ellipsoid is not enough.

  • Thank you for your answer. Below is using EPSG. EPSG:31276 to EPSG:4326 Is this shown parameters?? spatial-analyst.net/wiki/index.php?title=MGI_/… If it is right, let me know how to convert data with using this parameter. – Jermain Marthin Jan 11 '13 at 8:30
  • 1
    it depends on your data. If you don't know the EPSG or parameters of your data, you have to find out which fits better. There is not other way. You could also try creating you own coordinate system with these proj.4 code: +proj=tmerc +lat_0=0 +lon_0=18 +k=0.9999 +x_0=6500000 +y_0=0 +ellps=bessel +towgs84=550.499,164.116,475.142,5.80967,2.07902,-11.62386,0.99999445824 +units=m – Mario Miler Jan 11 '13 at 8:52
  • 1
    Your explanation is big help for me. It was succeed to convert data. Thank you very much!! – Jermain Marthin Jan 12 '13 at 8:28
  • I'm glad I could help :) – Mario Miler Jan 12 '13 at 21:43

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.