Paul A Malabad wrote:
I have found out that the DIgital orthos are Virginia State Plane Coordinate system. Through the metadata on the dvd, I found that although the discs read VASPCS North, The metadata actually refers to the VASPCS south. I metadata also refers to the units in US survey foot. whereas the epsg file refers to metre. I have tried using the information from the meta to create a separate projection, but it is not working correctly. Can you see anything wrong in my translation.

  PROJECTION
    "init=epsg:102746"
  END

Paul,

The ESRI coordinate system number 102746 is in US feet,
but I believe that the vector coordinates are in meter
based on the scale of the values.  So I'm not sure that 102746
is right for the vectors.  I think EPSG:32146 (VA SPCS North / meter)
or EPSG:32147 (VA SPCS South / meter) would be more appropriate.

EPSG 32146 can be described with the following proj.4 string:

 +proj=lcc +lat_1=39.2 +lat_2=38.03333333333333 +lat_0=37.66666666666666
   +lon_0=-78.5 +x_0=3500000 +y_0=2000000 +ellps=GRS80 +datum=NAD83
   +units=m +no_defs

    PROJECTION
      "proj=latlong"
      "ellps=GRS80"
      "datum=NAD83"
      "lat_0=36.333333334"
      "lat_1=36.766666667"
      "lat_2=37.966666667"
      "lon_0=-78.5"
      "units=ft"
    END

Note that this definition is ignoring the false easting and northing
which are very important.  In my fairly recent file VA SCPS South (ftUS)
is EPSG:2284 and maps to the PROJ.4 string:

  +proj=lcc +lat_1=37.96666666666667 +lat_2=36.76666666666667
    +lat_0=36.33333333333334 +lon_0=-78.5
    +x_0=3500000 +y_0=1000000.0
    +ellps=GRS80 +datum=NAD83 +to_meter=0.3048006096012192 +no_defs

Note the important +x_0 and +y_0 values.

So I *think* you want to use EPSG:32146 for the vector layer, and
EPSG:2284 for the raster layer.  Then you can set your map level
projection to whichever you wish.

Best regards,
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