HPGN Datum? (fwd)

[Bill Binko]

On Mon, 25 Apr 2005, Bill Binko wrote:

> On Mon, 25 Apr 2005, Dean C. Mikkelsen wrote:
>
> > Hi Bill,
> >
> > Have you applied the PROJECTION to the LAYER level on the .map file?
>
> I have, but I've been using the init=epsg instead of the actual
> parameters...
> >
> > What we are experiencing is the old NAD27/NAD83 problem. If PROJ.4 is
> > installed correctly, with the NADCON files, there should be no problem.
> >
> > What does your .map file look like?
>
> The relavent portions (I believe) are below.  There are several layers of
> each projection (as well as some others).  However, these two are the ones
> that I'm having trouble with.
>
> I'm beginning to wonder if that epsg:26759 really lines up with the
> parameters: perhaps I should put them in "by hand".
>

After looking into this, I'm a bit concerned: the .prj file has a false
easting of 500000, but the espg file from proj.4 has this:

<26759> +proj=tmerc +lat_0=24.33333333333333 +lon_0=-82 +k=0.999941
+x_0=152400.3048006096 +y_0=0 +ellps=clrk66 +datum=NAD27
+to_meter=0.3048006096012192 +no_defs  no_defs <>

Shouldn't the false easting and the x_0 match up?

Here's the .prj file:

PROJCS["NAD27 Florida State Planes, Western Zone, US Foot",
GEOGCS["North_American_Datum_1927",DATUM["D_North_American_1927",
SPHEROID["Clarke - 1866",6378206.4,294.9786982139006]],
PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],
PROJECTION["Transverse_Mercator"],
PARAMETER["latitude_of_origin",24.3333333333333],
PARAMETER["central_meridian",-82],
PARAMETER["scale_factor",0.9999411765],
PARAMETER["false_easting",500000],
PARAMETER["false_northing",0],UNIT["Foot_US",0.3048006]]

Thanks again
Bill