Hi list, i am using the PROJ.4 (cs2cs, GDAL/OGR, UMN MapServer) for transformation from CS to CS.
start-point (DHDN / GK 2 => epsg:31466) 5216100002;2552401,862;5616707,524 correct destination-point (ETRS89 / UTM 32 => epsg:25832) 32340408.033 5617072.487 example: cs2cs +init=epsg:31466 +to +init=epsg:25832 2552401.862 5616707.524 ----------------- Result with PROJ.4 version 4.5.0: 340411,268580576754175;5617068,431440304964781 => difference to the correct destination point in ETRS89: ~ 5 m => fine Result with PROJ.4 version 4.6 and 4.6.1: 340463.83 5617207.67 => not so fine / wrong => difference to the correct destination point in ETRS89: > 100m ---------------- ====> Why the difference in PROJ.4 Version 4.6 and 4.6.1 is the much? epsg-FILE: --- # ETRS89 / UTM zone 32N <25832> +proj=utm +zone=32 +ellps=GRS80 +units=m +no_defs <> # DHDN / Gauss-Kruger zone 2 <31466> +proj=tmerc +lat_0=0 +lon_0=6 +k=1 +x_0=2500000 +y_0=0 +ellps=bessel +datum=potsdam +units=m +no_defs <> --- ############### When i modified the epsg file like this (add parameter +datum=WGS84 to EPSG:25832): from # ETRS89 / UTM zone 32N <25832> +proj=utm +zone=32 +ellps=GRS80 +units=m +no_defs <> to # ETRS89 / UTM zone 32N <25832> +proj=utm +zone=32 +ellps=GRS80 +datum=WGS84 +units=m +no_defs <> ... the result is as expected and equal like by the PROJ.4 Version 4.5.0. --- cs2cs +init=epsg:31466 +to +init=epsg:25832 2552401.862 5616707.524 Result: 340411.27 5617068.43 ==> fine --- So is there a difference between PROJ.4-Versions (Version > 4.5 needs +datum-Parameter?) or am i doing something wrong? Best Regards, Greg -- Mit freundlichen Grüßen / Kind regards Gregor Fikoczek --------------------------------------- WhereGroup GmbH & Co. KG Siemensstraße 8 53121 Bonn Germany Gregor Fikoczek Email: [email protected] Fon: +49 (0)228 / 90 90 38 - 25 Fax: +49 (0)228 / 90 90 38 - 11 [email protected] www.wheregroup.com Amtsgericht Bonn, HRA 6788 ------------------------------- Komplementärin: WhereGroup Verwaltungs GmbH vertreten durch: Olaf Knopp, Peter Stamm --------------------------------------- _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
