Having a little trouble getting when I'm converting in Microsurvey dwg from UTM Zone 17 to a MTM zone 10 systems. Not sure if the scale factor is changing or not. Never really done this with Microsurvey. Still learning.
I have the scale factor, according to the crew, from the data collector using UTM cords. 0.999806
Any help or clarity would be great.
Dave
I would think that's it is highly unlikely that the scale factors would be the same.
PROJCS["NAD83 / MTM zone 10",
GEOGCS["NAD83",
DATUM["North_American_Datum_1983",
SPHEROID["GRS 1980",6378137,298.257222101,
AUTHORITY["EPSG",7019]],
AUTHORITY["EPSG",6269]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG",8901]],
UNIT["degree",0.01745329251994328,
AUTHORITY["EPSG",9122]],
AUTHORITY["EPSG",4269]],
UNIT["metre",1,
AUTHORITY["EPSG",9001]],
PROJECTION[Transverse_Mercator],
PARAMETER[latitude_of_origin,0],
PARAMETER[central_meridian,-79.5],
PARAMETER[scale_factor,0.9999],
PARAMETER[false_easting,304800],
PARAMETER[false_northing,0],
AUTHORITY["EPSG",32190],
AXIS[E(X),EAST],
AXIS[N(Y),NORTH]]
Loyal
I would see if you can figure out what MicroSurvey (or your favorite package) is doing. I am frustrated in general and in particular with ESRI inventing terms that seem to indicate something happened to the coordinates when in fact they may have just changed the label to make the metadata look "correct". I think the next ESRI user who says "reproject" needs a trip out to the woodshed!
The underlying thing is that the software would need to have the LLH and then just apply a new grid, IF that underlying geodetic data is correct (or can correctly be derived from the UTM coordinates), then you should be able to then get correct grid positions in any other geodetic system you can define.
SHG