Geotransformation is not valid

LT — Sat, 24 May 2014 16:33:54 GMT

Hi All,

I'm trying to find the area of my Denver, Colorado polygons in kilometers (km) and I think my data is in Decimal Degrees, so I need to project it before using calculate field to calculate the area.

My data properties say the following:
Data Type: Shapefile Feature Class
Shapefile: C:\foo.shp
Geometry Type: Polygon
Coordinates have Z values: No
Coordinates have measures: No

Geographic Coordinate System: GCS_WGS_1984
Datum: D_WGS_1984
Prime Meridian: Greenwich
Angular Unit: Degree

My specific questions are:

I think this means my data is in decimal degrees and I need to project it to get an accurate area measure in km. Does this sound correct?

I believe an appropriate coordinate system would be:

http://www.denvergov.org/?TabId=426422

http://www.spatialreference.org/ref/?search=Colorado

The project tool requires a coordinate system transformation and I selected NAD_1983_To_WGS_1984_5. Does this sound correct?

http://blogs.esri.com/esri/arcgis/2009/05/06/about-geographic-transformations-and-how-to-choose-the-right-one/

http://screencast.com/t/ARKUS3wQdf

Thank you for your help!

Re: Geotransformation is not valid

LT — Sat, 24 May 2014 16:43:31 GMT

Oops-- I got rid of the error by switching to

NAD_1983_StatePlane_Colorado_Central_FIPS_0502

instead of

NAD_1983_HARN_StatePlane_Colorado_Central_FIPS_0502

So you can ignore question #4. However my first three questions still remain.

Thanks again.

topic Re: Geotransformation is not valid in Geoprocessing Questions

Geotransformation is not valid

Re: Geotransformation is not valid