[gdal-dev] OGR Spatial reference shifting

[Frank Warmerdam]

Christiaan Janssen wrote:
> Does anyone else notice issues using the coordinate conversion in OGR 
> Spatial Reference. When I try to convert from a state plane system in US 
> feet to WGS84 Lat/Lon everything is shifted about 1.75 degrees to the 
> east. Specifically I'm converting Nad83 State Plane 101 (Alabama East)  
> US Feet to WGS84 Lat/Lon meters. Maybe this is a Proj.4 issue but I'm 
> not sure, any help would be greatly appreciated.

Christiaan,

There are many things that can go wrong.  :-(

Can you be more specific about exactly what you are doing, how you are
specifying the input and output coordinate system, what results you get
(ie. a sample point in and out) and why you believe the result is wrong?

1.75 degrees is a big error, so it clearly isn't a datum shifting error.
It could be a linear units issue (feet vs. meters) for either the
false easting/northings or the actual values being transformed.

Best regards,
-- 
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