[Qgis-user] problem reprojecting some shapefiles

[Simon Cropper]

On 21/01/14 22:44, Giacomo Fontanelli wrote:
> dear community
>
> I'm gonna report a problem that I observed frequently. I have polygon
> shapefile, downloaded from the net, representing the path of a
> satellite. I think this shapefile derive from a .kml, but I'm not sure.
> This layer is WGS84 EPSG:4326.
>
> I have also a layer in UTM 32N (EPSG:32632).
>
> If I work with the on the fly projection I can see both the layers
> correctly reprojected and positioned in EPSG 32632 (this must be the
> reference system of my project), but once I deflag the on fly projection
> and I try to reproject the WGS84 layer (Vector>Define projection) in UTM
> 32 N, the polygons are absolutely not overlayed.
>
> If I start again the on the fly projectio I don't get any overlay, the
> only way to reach a good positioning is to reproject again the first
> layer in the native reference system (WGS84) and using the on the fly
> reprojection.
>
> My impression is thar QGIS doesn't correctly reproject the shapefiles
> coming from .kml, am I wrong?
>
> Thank you very much
>
>
>
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>

Hi Giacomo,

It may be possible that  your shapefile does not have a spatial index 
(depends on tool used to convert from kml).

Try opening your original file in a new project projected in WGS84 
EPSG:4326, then reproject it to EPSG 32632 giving it a new name.

Open your original project in UTM 32N (EPSG:32632) and open the newly 
created satellite file.

Does this work?

-- 
Cheers Simon

    Simon Cropper - Open Content Creator

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