[Gvsig_english] project between datums

[ju]

thanks sergio but i already try !
in arcgis, there is a transformation from wgs84 to french NTF system, so 
between 2 different datum ( elipsoide)
in gv sig it does not work. if you try manually the transformation, it 
will not work  because there are only parameters x y and z so it can be 
used for transformation in the same datum only . but in my case, 2 datum 
are different.
it could work with epsg transformation ( all parametres are in epsg 
database) but when i choose epsg transformation in gvgis the box is 
empty.why ?

this probleme of transformation will occured in all country when someone 
would like to translate gps data ( in wgs84) to his own projected system 
( as ntf in france).
i hope there will be a ansnwer from develloper team but the job is 
already so good that i don't want to bother them !!!

thanks again ,
Julien


Sergio Clark a écrit :
> Hello Julien,
>
> About your second question, I think it doesn't exist in the JCRS 
> extension an implemented transformation between 4326 and 27572 system. 
> So you can reproject your shapes but using "Without transformation" 
> option, and it's not as exact as using "EPSG transformation" option. 
> Maybe this is the error you see.
>
> You can also introduce manualy the Transformation parameteres ("Manual 
> Transformation" option), if you know them..
>
> Best regards,
>
> Sergio.
>