Coordinate problem

Summary: there is disagreement between the actual Palo Alto data (using California State Plane Zone 3 feet) and the EPSG tables (used by PROJ.4, and hence the VTP software).  The disagreement is over the definition of the eastings and northings, feet vs. meters.

Details:

• problem: if the data is indeed in California State Plane Zone 3:
  • the coordinates should be in the range of (x=1,860,000  y=600,000)
  • instead they are in the range of (x=6,080,000  y=200,000)
• coordinate problem: if the data is indeed in California State Plane Zone 3:
  • according to PROJ.4, the coordinates should be in the range of (x=1,860,000  y=600,000)
  • instead they are in the range of (x=6,080,000  y=200,000)
  • they say that the former values are for CSP zone 3 NAD27, whereas the latter are NAD83
  • PROJ.4 says that the parameters for CSP zone3 NAD83 are:
    • standard parallel 1    38.4333333333
    • standard parallel 2    37.0666666666
    • center latitude    36.5
    • center longitude    -120.5
    • false easting    2000000
    • false northing    500000
  • if that's so, then Palo Alto at longitude -122.14 should be roughly 1,600,000... which PA says is NAD27
  • could the PROJ.4 parameters be wrong?
  • PCSCode = 26943 = "NAD83 / California zone 3"
  • EPSGGetProjTRFInfo
  • TRFCode = 10433 "California CS83 zone 3"
  • Datum: NAD 83
  • another reference says that the actual values are:
    • Projection: California State Plane, Zone III
    • Units: US Foot
    • 1st Std. Parallel: 37.0666
    • 2nd Std. Parallel: 38.4333
    • Longitude of Origin: -120.5
    • Latitude of Origin: 36.5
    • False Easting: 6561666.6666
    • False Northing: 1640416.6666
  • ...which would explain the PA data!!