[Qgis-user] Wrong reprojection if using different datums?

[Agustin Lobo]

I'm converting a shape of points in UTM 31N ED50
to lon,lat WGS84 using the save as... option
under File in QGIS. I've found that I get
the same lon, lat coordinates regardless
I select WGS84 or ED50 for the output shape. This
is not the case using Global Mapper:

QGIS UTM 31N ED50 POINT(449919.586269 4631874.109627)

TRANSFORMS TO LONGITUDE,LATITUDE:

QGIS ED50  POINT(2.396864 41.836439)
QGIS WGS84 POINT(2.396864 41.836439)

GlobalMapper  ED50  2.39686371° E	41.83643863° N
GlobalMapper  WGS84 2.39572870° E	41.83535625° N

I cannot guarantee that Global Mapper is right, of course,
but doesn't it make sense that the coordinates be
different in both datums? I suspect that proj4 (behind QGIS)
is not using the +towgs= field.

Any opinions on this problem?

Thanks

Agus
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