Hi Jaime,
to get transformation with towgs84 parameter working you have to use wgs84
ellipsoid. Transform from ETRS89 to wgs84 and second from wgs84 to ED50.
ST_Transform(ST_Transform( 25830_geom, 4326), 23030)
Gr
Ralf
Am Freitag 23 Juli 2010, 08:42:39 schrieb Jaime Fiers:
> Hello guys
>
> I hava a "little" problem with Postgis projection.
>
> I need get a reprojected view. Original data layer is in SRS=25830 (ETRS89
> UTM30) and view in SRS=23030 (ED50 UTM30)
>
> I try this:
>
> CREATE OR REPLACE VIEW vista_23030 AS
> SELECT id, transform_geometry("GEOMETRY", '+proj=utm +zone=30 +ellps=GRS80
> +units=m +no_defs
> +towgs84=131.0,100.3,163.4,1.2439999999999989,0.01999999999999998,1.1439999
> 999999988,-9.39 '::text,
> '+proj=utm +zone=30 +ellps=intl +units=m +nadgrids +no_defs'::text, 23030)
> AS "GEOMETRY"
> FROM capa_25830;
>
> (If we do not include "+nadgrids" we don't get anything, but that is not a
> problem).
> I always get a +-90 meter error.
>
> Can anybody help me.
>
> Thanks in advance
_______________________________________________
postgis-users mailing list
postgis-users@postgis.refractions.net
http://postgis.refractions.net/mailman/listinfo/postgis-users
