[postgis-users] Projections for Australia

[Mark Leslie]

2008/6/13 Shane Butler <shane.butler at gmail.com>:
> Dear list members,
>
> Can anyone recommend the appropriate meter-based projection to use for
> Australia?  I understand this is preferable to a lat-long projection
> (such as GDA94 which is what I normally use).  WGS84 has many zones
> and hence postgis complains about using different SRIDs when
> calculating distance between points in multiple WGS84 zones.  Any
> suggestions?
>
> Regards,
> Shane
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>

NSW Lambert, epsg:3308, would be appropriate for NSW, as you may
guess.  There are also the MGA zones 48-58 (epsg:28348-28358)  I'm not
aware of a single projection for all of Australia, likely due to the
warping as you move away from the central meridian.  Australia is big.
The distortion across one MGA zone usually isn't tragic, if your
points are near the boundary.  If you need to compare across more than
that I would think you're better off with something more geodetic,
like ST_distance_spheroid.

-- 
Mark Leslie
Geospatial Software Architect
LISAsoft
http://www.lisasoft.com/LISAsoft/SupportedProducts.html