Projection LAMBERT III (South of France) parameters

[Frank Warmerdam]

On 7/7/05, Selim Hernandez <pimpoumvlan at hotmail.com> wrote:
> Hello,
> 
> I can't find the right PROJECTION object's parameters in my .map file for
> coords in LAMBERT III (used for the South of France).
> 
> Though, when I translate these coords into the WGS 84 system (epsg:4326),
> it works fine.
> 
> Maybe the coords in the epsg file are wrong.
> 
> I used the following parameters and none of them worked :
> 
> "proj=lcc"
> "lat_1=44.10000000000001"
> "lat_0=44.10000000000001"
> "lon_0=2.33722917"
> "k_0=0.999877499"
> "x_0=600000"
> "y_0=200000"
> "a=6378249.2"
> "b=635651"
> "pm=paris"
> "units=m"

Selim,

There is an issue with the automated conversion from EPSG into 
PROJ.4 syntax for coordinate system using gradians for angular
values.  I think the angular->degree translation is happening twice.

Could you try using lat_0=49 and lat_1=49? 

Alternatively, it might be that the prime meridian is being improperly
applied.  If so, try setting lon_0=0.  

I do appologise for this botching of some complex coordinate systems.
I have had some open bug reports on it for some time, but haven't gotten
back to deal with it properly.

Best regards,
-- 
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