Projection

[Frank Warmerdam]

On Thu, 10 Mar 2005 16:08:55 +0100, Dirk-Jan Huisman
<d.huisman at ingbcc.nl> wrote:
> Hi all,
>
> My projection(British_National_Grid) file should be something like this:
>   PROJECTION
>     "proj=tmerc"
>     "lat_0=49"
>     "lon_0=-2"
>     "x_0=400000"
>     "y_0=-100000"
>     "k=0.999601272"
>     "ellps=Airy_1830"
>     "datum=D_OSGB_1936"
>     "to_meter=1"
>     "no_defs
>   END
>
> I'm using Windows2000 and Apache.
>
> With the install of Mapserver I copy proj/nad to C:\
>
> I have an unknown elliptical parameter ("ellps=Airy_1830") and unknown
> datum parameter("datum=D_OSGB_1936").

Dirk-Jan,

You can use the command "cs2cs -ld" to list available
datum names.  D_OSGB_1936 is not amoung them.
In fact, I don't know a good approximation to use for
the OSGB 1936 to WGS84 transformation.  If you have
a preferred 3 or 7 parameter transform you would like
to use, then provide it via the +towgs84 parameter.
Otherwise just drop the datum identfier and stick to
operating on the OSGB 1936 datum.

Best regards,
--
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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