Vyron Antoniou wrote:
Hi,
I think I'm missing something with SRIDs and transformations but I don't
really know what!!!
I have some POIs in WGS84 [ex. SRID=4326;POINT(-1.78103 51.09168)].
When I transform them into "OSGB 1936 / British National Grid" I use the
function: Transform(the_geom,27700) so the result for the above point is :
SRID=27700;POINT(415333.48161197 132490.68798396).
BUT.... if I use the transformation tool at
http://www.geograph.org.uk/latlong.php the result is:
[WGS84: 51:5.5008N 1:46.8618W]
Datum: Ordnance Survey Great Britain 1936
Easting/Northing: 415431,132508
Running some test with GIS software it seems that the latter is the
correct transformation
Any ideas?
Cheers!
Vyron
Hi Vyron,
The definition of UK SRID 27700 is currently wrong since it is missing
the OSGB36 datum definition. Unfortunately it only works correctly if
you are using PROJ >= 4.5, but if this is the case then simply append
"+datum=OSGB36" to the proj4text field and try again.
HTH,
Mark.
--
Mark Cave-Ayland
Sirius Corporation - The Open Source Experts
http://www.siriusit.co.uk
T: +44 870 608 0063
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