I was given some CAD Data and told it was in a 10TM projection, included in the meta data was the following information:

GEOGRAPHIC LOCATION: Latitude: 49:0:0

Longitude: 110:0:0

PROJECTION: 10 DEGREE TRANSVERSE MERCATOR

PROJECTION ID: 0202

CENTRAL MERIDIAN: 115

COMBINED SCALE FACTOR: 0

IGDS GLOBAL ORIGIN: X = 500000 Y = -5000000

DESIGN SCALE: 1000000

DATUM: NAD83

COMMENTS: 1:1,000,000 POSITION FILE

This is my attempt at the projection file:

PROJCS["10TM",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",-5000000.0],PARAMETER["Central_Meridian",115.0],PARAMETER["Scale_Factor",0.0],PARAMETER["Latitude_Of_Origin",49.0],UNIT["Meter",1.0]]

If someone could explain where I am going wrong that would be fantastic, keep in mind I am a relatively novice user,

Thanks in advance

GEOGRAPHIC LOCATION: Latitude: 49:0:0

Longitude: 110:0:0

PROJECTION: 10 DEGREE TRANSVERSE MERCATOR

PROJECTION ID: 0202

CENTRAL MERIDIAN: 115

COMBINED SCALE FACTOR: 0

IGDS GLOBAL ORIGIN: X = 500000 Y = -5000000

DESIGN SCALE: 1000000

DATUM: NAD83

COMMENTS: 1:1,000,000 POSITION FILE

This is my attempt at the projection file:

PROJCS["10TM",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",-5000000.0],PARAMETER["Central_Meridian",115.0],PARAMETER["Scale_Factor",0.0],PARAMETER["Latitude_Of_Origin",49.0],UNIT["Meter",1.0]]

If someone could explain where I am going wrong that would be fantastic, keep in mind I am a relatively novice user,

Thanks in advance

I see a few possibilities. Canadian data, right? The information doesn't match any of our existing 10TM definitions, unfortunately. First, change the central meridian to -115. (115W).

Also I would try changing the latitude of origin to zero. I think geographic location just identifies the area of the data, and may not have anything to do with the projection parameters. With the latitude of origin set to the equator, Y values will be around 5-6 million. However, with a -5000000 m false northing, that will reduce the size of the Y values.

Lastly, change the scale factor to 1.0. Scale factor is applied as a multiplier to the numbers coming out of the algorithm, before the false easting and false northing values are added.

Melita