Rick, I believe that Google Earth always expects the data to be EPSG:4326, and assumes this, regardless of what the datum really is. It sounds like the results you are getting line up with this.
Regards, David On Sun, Jan 9, 2011 at 9:20 AM, Rick Workman <[email protected]> wrote: > I have imported a shape file into GeoServer (2.0.2 or 2.1-beta3) whose > native and declared SRS is EPSG:2019 (NAD27(76) / MTM zone 10 ). When I view > the layer from a WorldWind client whose WMS request uses EPSG:4236 (WGS 84) > overlaid on a MS virtual earth image layer, it appears to be offset from > the image. And I get the same effect using Google Earth as a client. > > Now if I use Quantum GIS to reproject the original shape file to EPSG:4326 > and import that shape file into Geoserver, the resultant layer seems to be > correctly aligned. > > If I go back to the layer definitions in the Geoserver admin interface, the > computed Lat/Lon Bounding Box for the two layers is slightly different: > > Original (EPSG:2019): -79.64, 43.578, -79.115, 43.854 > QGIS altered (EPSG:4326): -79.639, 43.581, -79.115, 43.855 > (correct values, as far as I can tell) > > The discrepancy between the two sets of values seems to correspond fairly > well with the offset displayed by the clients (WorldWind and Google Earth). > > So unless I'm missing some setting in the layer definition process, it > looks like Geoserver is not accurately projecting at least the EPSG:2019 > SRS. > > On further investigation, it I can't find too many SRS systems that do seem > to work. For example, the same shape file converted (in QGIS) to a native > SRS of EPSG:26717 ("NAD27 / UTM zone 17N") has slightly larger errors: > > EPSG:26717: -79.643, 43.575, -79.113, 43.862 > > and EPSG:32190 ("NAD83 / MTM zone 10") seems to have correct native > bounding box lat/lon values, but the computed Lat/Lon bounding Box is > nonsensical: > > EPSG:32190: -82.238, 0, -82.238, 0 > > > Any ideas what's going on? > > > Rick > > > > > ------------------------------------------------------------------------------ > Gaining the trust of online customers is vital for the success of any > company > that requires sensitive data to be transmitted over the Web. Learn how to > best implement a security strategy that keeps consumers' information secure > and instills the confidence they need to proceed with transactions. > http://p.sf.net/sfu/oracle-sfdevnl > _______________________________________________ > Geoserver-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/geoserver-users >
------------------------------------------------------------------------------ Gaining the trust of online customers is vital for the success of any company that requires sensitive data to be transmitted over the Web. Learn how to best implement a security strategy that keeps consumers' information secure and instills the confidence they need to proceed with transactions. http://p.sf.net/sfu/oracle-sfdevnl
_______________________________________________ Geoserver-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geoserver-users
