I'm sure this has been asked before....
I have grid parameters of a local projection (Mine grid) based on the Map Grid of Australia:
Grid Name : Local Grid
Central Scale Factor 1.000000
Origin Local Grid Easting 800,400.025
Origin Local Grid Northing 300,500
Origin MGA Zone 50 Easting (GDA94) 700,000.498m
Origin MGA Zone 50 Northing (GDA94) 6,900,600.233m
Orientation at Origin 31o24’43”MGA
Now to add a new grid these are the steps I am using:
1. Data Frame Properties
2. Coordinate system tab
3. New Projected coordinate system
4. Change Projection name from Transverse Mercator to "Local"
5. Enter the above parameters into the "Values" area, where:
False Easting = Origin Local Grid Easting 800,400.025
False Northing = Origin Local Grid Northing 300,500
Scale Factor = 1.0000000
Azimuth = Orientation at Origin 31o24’43”MGA, but I put in decimal degrees of 31.411944
Longitude of center = Origin MGA Zone 50 Easting (GDA94) 700,000.498m - converted to Geographic coords and to decimal degrees (GDA94)
Latitude of center = Origin MGA Zone 50 Northing (GDA94) 6,900,600.233m - converted to Geographic coords and to decimal degrees (GDA94)
Unit = meter
Meters per unit = 1
Geographic Coordinate system = I changed this to the MGA Zone 50 (GDA94) grid...which the local grid is based on.
I don't seem to get real accurate results.
The points are a fair way off where they should be.
Have I done everything correct ?