Incorrect reference

[hobu]

From: "D'Eramo, Massimo" <Massimo.D'Eramo@garmin.com>
Date: April 2, 2012 8:48:42 AM CDT
To: "hobu.inc@gmail.com" <hobu.inc@gmail.com>
Subject: Attention Mr. Howard Butler - wrong entry list in Spatialreference.org for Gauss-Boaga

Hello Mr. Butler,
I apologize if I write you through this address but I couldn’t find a reference mailbox address in Spatialreference.org website.
 
I have found a mistake in Italy Gauss-Boaga East (4686) reference system. The central meridian for this projection is 15° East of Greenwich, while you report 9° East.
Now, 9°East of Greenwich is the central meridian for Gauss-Boaga West (4685), so this error brings a very large systemic error if used.
 
System definition for 4686 should therefore be changed as following:
 
PROJCS["unnamed",
    GEOGCS["International 1909 (Hayford)",
        DATUM["unknown",
            SPHEROID["intl",6378388,297]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",15],
    PARAMETER["scale_factor",0.9996],
    PARAMETER["false_easting",2520000],
    PARAMETER["false_northing",0]]
 
 
I would kindly ask you to correct the issue and confirm to me. Also, I see that both Gauss-Boaga reference systems are classified as “unnamend” in PROJCS field. I would suggest to assign the names of “Gauss-Boaga Ovest” to the West zone (4685) and “Gauss-Boaga Est” for the East zone (4686). These are the most commonly used names for the two systems here in Italy. If you prefer an English naming, simply use “Gauss-Boaga West” and “Gauss-Boaga East”. Italian people will anyway be able to understand it…
 
Thanks in advance
 
Best regards
 
 
Massimo D’Eramo