[OSRS-PROJ] EPSG file and Gauss-Boaga Italy definition

[Markus Neteler]

Dear list members,

while comparing our definition of Gauss-Boaga (Italy)
in GRASS GIS and the definition ins the epsg file of PROJ4
we found a surprising (to me) difference:

EPSG file:
# Monte Mario (Rome) / Italy zone 1
<26591> +proj=tmerc +lat_0=0 +lon_0=21.45233333333333 +k=0.999600
+x_0=1500000 +y_0=0 +ellps=intl +pm=rome +units=m +no_defs no_defs <>
                                                                                                                            
# Monte Mario (Rome) / Italy zone 2
<26592> +proj=tmerc +lat_0=0 +lon_0=27.45233333333333 +k=0.999600
+x_0=2520000 +y_0=0 +ellps=intl +pm=rome +units=m +no_defs no_defs <>
                                                                                                                            
According to what we have used so far in GRASS,
the lon_0 values differ:

As far as I know, it should be
<26591>: +lon_0=9.0
<26592>: +lon_0=15.0

Both lon_0=21.45 and lon_0=27.45 are outside of Italy.

Probably I am missing something.
A hint is most welcome,

 Markus Neteler

-- 
Markus Neteler     <neteler at itc.it>       http://mpa.itc.it
ITC-irst, Istituto per la Ricerca Scientifica e Tecnologica
MPBA - Predictive Models for Biol. & Environ. Data Analysis
Via Sommarive, 18        -       38050 Povo (Trento), Italy
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