Raster projection shift

[Frank Warmerdam]

On 9/8/05, Alessandro Pasotti <ale.pas at tiscali.it> wrote:
> Hello,
> 
> I have a problem with a raster file ETM+, it is a GeoTIFF format, there is a
> shift (about 50m) with my shapefiles (ported to postgis), please see the
> attached image.
> 
> postgis srid is 26591

Alessandro, 

PROJ.4 does not "know" what datum shift to use for the Monte
Mario datum underlying EPSG:26591.  You will need to research
appropriate towgs84 value to use and apply them in the epsg 
lookup file. 

This offset is almost certain related to datum shifting (or a lack
thereof). 

Best regards,
-- 
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