[postgis-users] Bugus SRS

[strk at refractions.net]

Nicolas, we just changed the entry you pointed our attention on:
SRID=27582

You reported it worked for you with entries shipped with postgis 
pre 1.0.0:

On Wed, Feb 02, 2005 at 06:50:46PM +0100, RIBOT, Nicolas wrote:
> Transform() is not buggy.
>
> To follow my previous post, and thanks to Michael Michaud that noticed the
> differences, the spatial_ref_sys.sql provided with postgis 1.0 RC is not the
> same as the one provided with the previous Postgis versions, at least for
> french projections.
> Namely, for SRID=27582, the proj4 parameters in postgis 0.8:
>
> +proj=lcc
> +lat_1=46.8
> +lat_0=46.8
> +lon_0=2.337229166666667
> +k_0=0.99987742
> +x_0=600000
> +y_0=2200000
> +a=6378249.2
> +b=6356514.999904194
> +pm=2.337229166666667
> +units=m

That entry already had a lon_0 != 0.

Since these entries are extracted by a script in gdal/ogr
I think it's worth fixing them in the source data repository
first.

Frank, did you check this out lately ?

--strk;

On Wed, May 04, 2005 at 10:05:52PM +0200, El Nico wrote:
> > Nicolas, I'm trying to figure out what to do with these *bogus* entries
> > in spatial_ref_sys.
> > The problem is that there are more then a single entries for Paris,
> > so I think all of them are bogus.
> > Another problem is: "would a newer PROJ4 version correclty interpret the
> > new paramaters?".
> > What PROJ4 version are you using ? Could you check if newer PROJ4 give
> > a different result ?
> > --strk;
> 
> Hi Strk,
> 
> I'm sorry to answer to your email so lately, but I was unable to
> install the latest postgis version before now.
> 
> So I compiled postgresql 8.0.2 and postgis 1.0.0 on Windows XP:
> 
> PostgreSQL 8.0.2 on i686-pc-mingw32, compiled by GCC gcc.exe (GCC)
> 3.2.3 (mingw special 20030504-1).
>  POSTGIS="1.0.0" GEOS="2.1.1" PROJ="Rel. 4.4.9, 29 Oct 2004" USE_STATS
> DBPROC="0.3.0" RELPROC="0.3.0"
> 
> When checking SRS definitions for french projections (SRID from 27500
> to 27594) I notice the error mentionned in the previous messages of
> this thread is still here:
> The "+long_0" EPSG parameter indicates a non-zero value (2.33722917)
> though the prime meridian is Paris (+pm=paris).
> 
> I think the right +long_0 value should be 0 if prime meridian is Paris.
> 
> After correcting the values and testing a reprojection, result seems
> to be correct.
> 
> Nicolas
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