Hi,
I'm having problems trying to transform from the above datums using
the epsg-wkt module (not the access one) distributed along with uDig.
The problem is, the epsg.properties file does contain the following
definition of ed50:
4154=GEOGCS["ED50(ED77)",DATUM["European_Datum_1950_1977",SPHEROID["International
1924",6378388,297,AUTHORITY["EPSG","7022"]],AUTHORITY["EPSG","6154"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4154"]]
As you can see, the TOWGS84 parameters are missing!
Now, as far as I know the epsg.properties file have been derived from the
spatial_ref_sys table of postgis, which in turn has been derived from the proj.4
library (that one is a guess). Turns out that neither postgis have these
parameters, not even in the last version, so everyone trying to do an ED50 ->
WGS84 transform under Postgis will fail as well.
Can someone clarify how should I proceed, given that I cannot use the MSAccess
epsg file? Did anyone try to re-generate the epsg.properties file from the
official EPSG database?
Or, does someone have some more info on how the postgis spatial_ref_sys table
have been populated?
Cheers
Andrea Aime
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