Hi Nicolas, That is not exactly true.
QGIS can very well cope with grid-shift based transformations. This requires an adequate grid shift file (a gsb file), which should be placed in the folder share/proj National mapping agencies typically provide these grid-shift files. As an example, our Swiss NMA provides these at http://www.swisstopo.admin.ch/internet/swisstopo/en/home/products/software/products/chenyx06.html QGIS automatically detects whether a grid shift file is necessary for a transformation and if the appropriate gsb files is present it is used. The accuracy of the transformation then depends on the grid-shift file accuracy (resolution). The grid shift files can be used both for reprojecting vector and raster data. Greetings, Andreas On 2016-03-31 15:54, Nicolas Cadieux wrote: > Hi, > It is my understanding that the parameters used in QGIS for that > transformation are not sufficient and will simply lead to a change in EPGS > code number with no actual changes to the coordinates. > > If you are dealing with data in the 20k to 250k (like topo maps, SRTM), you > can go ahead with that. Difference between both projection are basically due > to continental drift and the addition of the third dimension. > > For anything submeter (Lidar, high precision GPS) I recommend using a more > precise software. I know that nrcan has good free tools for changing > projection but I don't know if they handle anything else then points (TRX) I > think. Look at the links below for more information if needed. File is > included in attachment. > > Nicolas > > http://www.nrcan.gc.ca/earth-sciences/geomatics/geodetic-reference-systems/tools-applications/10925 > > > https://www.google.ca/url?sa=t&source=web&rct=j&url=http://www.naref.org/transf/nad83_geomatica2006.pdf&q=csrs98%20nad83&ved=0ahUKEwiex4GHiOvLAhUEdx4KHb0NAwcQFggpMAU&usg=AFQjCNHa-HRpS8Hcc1j74dAysyxgobNY1w&sig2=RRPnudp1rMyhmKYd7vbdoA > > On Mar 31, 2016 8:20 AM, "Joris Hintjens [via OSGeo.org] " <[hidden email]> > wrote: > simply save the layer as a new one. "save as". you will be asked to enter the > new CRS. > > joris > > Op 30 mrt. 2016, om 06:06 heeft Azzurra Lentini <<a > href="/user/SendEmail.jtp?type=node&node=5258986&i=0">[hidden > email]> het volgende geschreven: > > Hallo to all, > do you know how I can transform vectorial data from NAD83 (CSRS98) to UTM > wgs84? > do you think if I do with reproject it would be ok?? or what u suggest?? > > thanks a lot > -- > > Dr. Hydrogeologist > AZZURRA LENTINI > Expert of evaluation environmental hazards > GIS application > Haity Mobile Tel: 0050946057393 > ++++++++++++++++++++++++++ > Italy Mobile Tel.: **(39) 338 24 40 676 > ++++++++++++++++++++++++++ > SKYPE azzurrahydro > ++++++++++++++++++++++++++ > <a > href="/user/SendEmail.jtp?type=node&node=5258986&i=1">[hidden > email] > ++++++++++++++++++++++++++ > *Par respect pour l'environnement,* > > *n'imprimez ce mail qu'en cas d'absolue nécessité* > > _______________________________________________ > Qgis-user mailing list > <a > href="/user/SendEmail.jtp?type=node&node=5258986&i=2">[hidden > email] > List info: http://lists.osgeo.org/mailman/listinfo/qgis-user > Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-user > _______________________________________________ > Qgis-user mailing list > <a > href="/user/SendEmail.jtp?type=node&node=5258986&i=3">[hidden > email] > List info: http://lists.osgeo.org/mailman/listinfo/qgis-user > Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-user > > ------------------------- > > If you reply to this email, your message will be added to the discussion > below: > http://osgeo-org.1560.x6.nabble.com/vector-shp-from-NAD83-CSRS98-to-UTM-WGS84-tp5258754p5258986.html > > To start a new topic under Quantum GIS - User, email > [email protected] > To unsubscribe from Quantum GIS - User, <a > href="http://osgeo-org.1560.x6.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_code&node=4125267&code=bmljb2xhcy5jYWRpZXV4QGFyY2hlb3RlYy5jYXw0MTI1MjY3fDYzNDQ4MjQxNg==";>click > here. > <a > href="http://osgeo-org.1560.x6.nabble.com/template/NamlServlet.jtp?macro=macro_viewer&id=instant_html%21nabble%3Aemail.naml&base=nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.view.web.template.NodeNamespace&breadcrumbs=notify_subscribers%21nabble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_email%21nabble%3Aemail.naml"; > style="font:9px serif">NAML NAD83_GEOMATICA2006.PDF (6M) Download Attachment [1] ------------------------- View this message in context: Re: vector shp from NAD83 (CSRS98) to UTM WGS84 [2] Sent from the Quantum GIS - User mailing list archive [3] at Nabble.com. _______________________________________________ Qgis-user mailing list [email protected] List info: http://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-user Links: ------ [1] http://osgeo-org.1560.x6.nabble.com/attachment/5259001/0/nad83_geomatica2006.pdf [2] http://osgeo-org.1560.x6.nabble.com/vector-shp-from-NAD83-CSRS98-to-UTM-WGS84-tp5258754p5259001.html [3] http://osgeo-org.1560.x6.nabble.com/Quantum-GIS-User-f4125267.html
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