I should preface this by saying I'm a software developer, not a GIS specialist. However, I've been working on GIS applications for some time now using standard tools and libraries. For this project, I'm developing a workspace using FME Desktop attached to a PostGIS database.

So I'm trying to reproject vector data containing lat/long coordinates (based on NAD27) to a Cartesian coordinate system with x and y values based on some sane unit of measure…something from which I can compute areas. It's been suggested that I need a coordinate reference system based on the Albers Equal-Area projection for this purpose. So I've chosen EPSG:5069, since it seems to have everything I need for the Continental U.S.

Using the FME Reprojector transformer, I fully expected the output to contain coordinates from EPSG:5069's declared origin and scaled to meters (since the WKT for 5069 contains the declaration **UNIT["m", 1.0]**). However, all output coordinates are still in lat/long, with units in degrees. Therefore, the subsequent area calculations produce nonsense results. At this point, I have no idea whether the problem is in FME, PostGIS, or my understanding of EPSG:5069.

For the sake of completeness, I should mention that EPSG:5069 was missing from the spatial_ref_sys table in the default PostGIS installation, so I had to insert the missing record. I got the missing WKT for the srtext field from this page:

And I got the missing proj4text field data by capturing the output from this PROJ.4 command:

**cs2cs -v +init=epsg:5069**

And finally, here's the CSV record that I loaded into spatial_ref_sys:

**5069 EPSG 5069 PROJCS["NAD27 / Conus Albers", GEOGCS["NAD27", DATUM["North American Datum 1927", SPHEROID["Clarke 1866", 6378206.4, 294.9786982138982, AUTHORITY["EPSG","7008"]], TOWGS84[2.478, 149.752, 197.726, 0.526, -0.498, 0.501, 0.14129139227926102], AUTHORITY["EPSG","6267"]], PRIMEM["Greenwich", 0.0, AUTHORITY["EPSG","8901"]], UNIT["degree", 0.017453292519943295], AXIS["Geodetic longitude", EAST], AXIS["Geodetic latitude", NORTH], AUTHORITY["EPSG","4267"]], PROJECTION["Albers Equal Area", AUTHORITY["EPSG","9822"]], PARAMETER["central_meridian", -96.0], PARAMETER["latitude_of_origin", 23.0], PARAMETER["standard_parallel_1", 29.5], PARAMETER["false_easting", 0.0], PARAMETER["false_northing", 0.0], PARAMETER["standard_parallel_2", 45.5], UNIT["m", 1.0], AXIS["Easting", EAST], AXIS["Northing", NORTH], AUTHORITY["EPSG","5069"]] +proj=aea +lat_1=29.5 +lat_2=45.5 +lat_0=23 +lon_0=-96 +x_0=0 +y_0=0 +datum=NAD27 +units=m +no_defs +ellps=clrk66 +nadgrids=@conus,@alaska,@ntv2_0.gsb,@ntv1_can.dat**

So I'd like a little help figuring out what I'm doing wrong, or at least which architectural layer I should focus my attention on. Even vague hints would be welcome!

- Kevin