Yes, actuallyI am reprojecting rasters from Gauss Boaga Roma 40 Monte
Mario zone 2 to ED50UTM33.
Errors are huge if I use 102092, but they are very small using 3004.
Further research lead me to discover even more, appearingly identical,
reference systems:
- Monte Mario Italy 2.prj (codice EPSG 3004);
- Monte Mario (Rome) Italy 2.prj (codice EPSG 26592);
- Roma 1940 Gauss Boaga Est.prj (codice EPSG 102094),
This is even more confusing, and will require some more studying.
Regards,
Paolo
Il 07/11/2013 10:37, G. Allegri ha scritto:
As you can see, 102092 has the average transformation parameters to
WGS84, which brings some more precision during datum transformation. I
suppose you're reprojecting the data to some different CRS.
giovanni
Il 07/nov/2013 08:33 "Paolo" <[email protected]
<mailto:[email protected]>> ha scritto:
Oops... I forgot the most important part in my first post. Here
are the edfinitions:
EPSG 3004 - Monte Mario / Italy zone 2:
+proj=tmerc +lat_0=0 +lon_0=15 +k=0.9996 +x_0=2520000 +y_0=0
+ellps=intl +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68
+units=m +no_defs
EPSG 102092 - Monte_Mario_Italy_2:
+proj=tmerc +lat_0=0 +lon_0=15 +k=0.9996 +x_0=2520000 +y_0=0
+ellps=intl +units=m +no_defs
3004 works well with my data, while 102092 does not.
There appears to be a relatively large shift, in the order of tens
or hundreds meters,monstly along the north - south direction.
Thanks
Paolo
Il 07/11/2013 00:47, G. Allegri ha scritto:
In QGIS they appear having the same definition, Could you paste
the 102092 definition that you have?
giovanni
2013/11/6 Paolo <[email protected] <mailto:[email protected]>>
Hello,
I am a relatively recent QGIS user. I am at the moment using
version 2.0 - Dufour.
I would like to ask a simple question about two different
datums I am experiencing problems with.
They are: EPSG 102092 and EPSG 3004.
Accordinf to my (short) research, they are supposed to be
exactly the same datum, but the definitions in QGIS are
different.
If I use 3004, the specific data set I'm using will overlap
properly with the other datasets, but it will not if I use
102092.
Can anybody help me getting a better understanding of this
behaviour?
Thanks
Paolo
_______________________________________________
Qgis-user mailing list
[email protected] <mailto:[email protected]>
http://lists.osgeo.org/mailman/listinfo/qgis-user
--
Giovanni Allegri
http://about.me/giovanniallegri
blog: http://blog.spaziogis.it
GEO+ geomatica in Italia http://bit.ly/GEOplus
_______________________________________________
Qgis-user mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/qgis-user
