Could it be this: http://proj4.org/faq.html#changing-ellipsoid-why-can-t-i-convert-from-wgs84-to-google-earth-virtual-globe-mercator
? The further you get from the equator, the more obvious the discrepancy on the Y axis. Best, Ben On 05/03/18 09:38, Idan Miara wrote: > Hi, > > I might have found a bug related to transformation of layer CRS > from EPSG:3857 (Pseudo Mercator) to EPSG:4325 (WGS84 Geo). > I'm attaching a few images to demonstrate the issue. > > Steps to reproduce: > I've load OSM in QGIS 2.18.16 (or 3.0,same results) > via Tile Server (XYZ): > https://a.tile.openstreetmap.org/{z}/{x}/{y}.png > <https://a.tile.openstreetmap.org/%7Bz%7D/%7Bx%7D/%7By%7D.png> > > Then set the CRS to EPSG:4326 (WGS84 Geo) > > I've also loaded a global bounds vector layer (EPSG:4326) > > In scale 1:100,000,000 it seems that the Pseudo Mercator transformation > to 4326 is flawed, as the OSM and the vectors are not aligned. > In scale 1:50,000,000 it seems OK when the extent is the middle of the > map, but if I pan to the south/north it seems distorted again. > > If I set the project CRS to EPSG:3857 (Pseudo Mercator) as the CRS of > the OSM tiles, so the vector layer would be transformed instead, then > they do align in all scales (picture with the blue vector layer). > > It doesn't look like a problem of precision of the transformation from > 3857 to 4325 because it's way off. > Is that a bug or am I missing something here? > > Kind regards, > Idan. > > > > _______________________________________________ > Qgis-user mailing list > Qgis-user@lists.osgeo.org > List info: https://lists.osgeo.org/mailman/listinfo/qgis-user > Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user > -- Dr. Benjamin Ducke Deutsches Archäologisches Institut (DAI) Zentrale Berlin, IT-Referat * Projekt "Stunde Null" * _______________________________________________ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user