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In the description of gdaltransform this example is given:

gdaltransform -s_srs EPSG:28992 -t_srs EPSG:31370 177502 311865
Produces the following output in meters in the "Belge 1972 / Belgian Lambert 72" projection:
244510.77404604 166154.532871342 -1046.79270555763

If I try this I get

gdaltransform -s_srs EPSG:28992 -t_srs EPSG:31370 177502 311865  
244422.238366377 165970.245450285 0

If I write the coordinates into a single point-shape, same result when applying ogr2ogr

ogr2ogr -s_srs EPSG:28992 -t_srs EPSG:31370 out31370.shp in28992.shp

Any ideas what I'm doing wrong?

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1 Answer

up vote 2 down vote accepted

Funnily, with GDAL 1.9.0 I get:

244296.723070577 165937.350438408 1.6097514744356

Which is different again! I suspect there's a problem with the Proj4 database that has been fixed at one time or another, judging by this (long) thread I found:

http://lists.maptools.org/pipermail/proj/2010-January/005016.html

This email in the thread has the parameters that seem to match the ones that come with my version of GDAL:

+proj=lcc +lat_1=51.16666723333333 +lat_2=49.8333339 +lat_0=90 +lon_0=4.367486666666666 +x_0=150000.013 +y_0=5400088.438 +ellps=intl +towgs84=-106.8686,52.2978,-103.7239,0.3366,-0.457,1.8422,-1.2747 +units=m

So they might be the right ones, but without some real-world data to try it on, there's no way of knowing.

Addendum

It's easy to find out which version of GDAL you're using, just provide the --version switch to any of the GDAL tools.

It is equally easy to use Proj4 projection strings with any of the _srs parameters, simply put it in quotes where you had EPSG:nnnnn, e.g.:

gdal_transform -s_srs EPSG:28992 -t_srs "+proj=lcc +lat_1=51.16666723333333 +lat_2=49.8333339 +lat_0=90 +lon_0=4.367486666666666 +x_0=150000.013 +y_0=5400088.438 +ellps=intl +towgs84=-106.8686,52.2978,-103.7239,0.3366,-0.457,1.8422,-1.2747 +units=m"
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Thanks for the link. I'm using fwtools V2.4.7, I have no idea which gdal-version it is in there. Sorry, I'm totally new to this stuff; could you write down how you run gdaltransform with your parameters? –  user6848 Apr 11 '12 at 7:26
1  
You should drop FWTools and get a newer build, yours is way out of date. There are installers for Windows here, so it's not the same as FWTools but easy enough: gisinternals.com/sdk –  mdsumner Apr 11 '12 at 10:21
1  
Ah, great. I have installed the new version (I had 1.7.0b2 before) and now my real world data is perfectly there where it should be. Thank you!! (and as a little contribution: it is --version) –  user6848 Apr 11 '12 at 10:51
    
Fantastic! I've fixed the --version typo. Would you mark the answer as "accepted" please? –  MerseyViking Apr 11 '12 at 11:02
    
Accepted! I have to get used to this ambigious forum :) –  user6848 Apr 11 '12 at 15:22
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