AutoCAD Civil 3D

[#1]

anyone know anything about using the new geoid that was released http://www.ngs.noaa.gov/GEOID/USGG2012/

supossedly more accurate / corrected location data. Just what we need right... another coordinate system

[#2]

A Geoid is not a coordinate system, from NOAA:

geoid: The equipotential surface of the Earth's gravity field which best fits, in a least squares sense, global mean sea level

Bill

[#3]

Link does not work.

[#4]

The Geoid model is used to correct GPS observations WGS84 Ellipsoidal height to the local Orthometric height (Mean Sea Level).  GEOID12. Changes impacted regions in the states of Alabama, Mississippi, Louisiana, Texas, Oklahoma, and Wisconsin. http://www.ngs.noaa.gov/GEOID/GEOID12/.

The Geiod Models are used in Software such as Leica LGO or Move3 to correct raw GPS observations to the local Orthometric height. In elevation critical applications observations should be made on at least 3 Bench Marks in the work area to establish the Plane of the local spheroid, and the field data adjusted.

Jim

E&P Geophysics Group

Matrix3Dsurveys

[#5]

I thought it was part of a coordinate system. As you mentioned, in order to get satalite aquired possitioing on to a ortho you need a geoid moodel, so in effect it is part of a coordinate system right?

I wasn't really asking a question, until now.