[Proj] Reprojection help for a newbie (Lambert Conformal Conic)

[Anthony Dunk]

Hi Richard,

This is the code I use to generate a LCC projection (The Format
statement is part of CString which is an MFC class, but its the same
structure as printf() ):

        CString sProjCmd;
        sProjCmd.Format("+proj=lcc +lat_1=%.16g +lat_2=%.16g
+lat_0=%.16g +lon_0=%.16g +x_0=%.16g +y_0=%.16g ",
			pCS->GetProjection()->GetStdParallel1(),
			pCS->GetProjection()->GetStdParallel2(),
			pCS->GetProjection()->GetOriginLat(),
			dOriginLon,
			dFalseEasting,
			dFalseNorthing);

The parameters for the conformal conic projections supported in the
MAPINFO.PRJ file which comes with MapInfo are:

The parameters for the regional Australian Conformal Conic are:
"Conformal Projection (Australia)", 3, 0, 0, 132.5, -10, -21.5, -33.5,
0, 0

"Australian Lamberts Conformal Conic", 3, 12, 7, 147, 0, -32.666,
-35.333, 1000000, 10000000

"Australian Lamberts Conformal Conic (AGD66)", 3, 12, 7, 135, -24, -18,
-36, 0, 0

The format of these lines is:
"Name", projection_code, datum_code , units_code, origin_lon,
origin_lat, std_parallel_1, std_parallel_2, false_easting,
false_northing

Where:
Projection code 3 = Lambert Conformal Conic
Datum code 12 = AGD66
Units code 7 = Metres

I hope this is some help.

Cheers,
Anthony.

--- Richard Chirgwin <rchirgwin at ozemail.com.au> wrote:

> Greetings,
> 
> I'm using Grass-GIS, but with a reprojection I was told this list was
> 
> the best place to go.
> 
> I have a lot of existing maps using a simple lat-long location in
> AGD84 
> - that is, Australian ellopsoid, zone 0.
> 
> I'm now trying to import some maps that were put together using the 
> Lambert Conformal Conical projection with the following project info:
> Lamberts Conformal Conic, 3, 13, 7, 134, -27, -15, -39, 5000000,
> 5000000
> 
> I can't get the LCC-based map to reproject into the lat-long region
> and 
> display correctly. I've tried cs2cs, but the LCC map is still 
> out-of-shape compared to the ADG84 map. So clearly I'm doing
> something 
> wrong. Can anyone tell me the correct use of cs2cs for reprojecting
> in 
> and out of LCC?
> 
> Richard
> 
> More data if needed:
> - For the LCC maps, the pointsfile contains lat-long columns, so I
> can 
> get a file that looks like this:
> (x, y, x1, y1)
> 4984067.30681393 5349948.72155986 133.82 -23.77
> 
> - However, for the lat-long files, I only have lat-long data (not the
> 
> corresponding x-y values which would easily locate the lat-long info
> in 
> the LCC space).
> - As well as cs2cs, I have tried georectifying the points file
> towards 
> the LCC projection, without success.
> _______________________________________________
> Proj mailing list
> Proj at lists.maptools.org
> http://lists.maptools.org/mailman/listinfo/proj
> 


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