[postgis-users] Which SRID to choose?

[Markus Schaber]

Hi, Homme,

On Thu, 25 Mar 2004 10:09:47 +0000
Homme Zwaagstra <hrz at geodata.soton.ac.uk> wrote:

> > We currently get our geometry data in longitude/latitude format in
> > degrees (e. G., 'POINT(8.53951 47.37704)' is Z?rich).
> 
> Have you had a look at the spatial_ref_sys table?  This is created if
> you load the spatial_ref_sys.sql file when you enable PostGIS on your
> database. I find this to be a valuable source of projection and SRID
> information, especially as it lists the proj4 options for each SRID.

Yes, we had, but we were rather confused by the pure amount of reference
systems without any further pointers to explanation.
 
> > Our two data sources currently are GPS receivers and Shapefiles from
> > ArcView Premium.
> 
> Your GPS receivers are likely to return coordinates in the WGS 1984
> system. The EPSG (http://www.epsg.org/) code for this is 4326.

Thanks, I now found out that GPS really seems to use the WGS 1984
coordinate sstem.

Thanks for your additional Pointers to information, this seems very
helpful.

Greets,
Markus
-- 
markus schaber | dipl. informatiker
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