Starnet coordinate systems

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Software, CAD & Mapping

Last Post by bill-c 3 months ago

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john-hamilton

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I use Star*Net for certain projects, Geolab for others. But something in Star*Net always puzzled me.

When setting up a coordinate system, they have "State Planes, NAD83" and "State Planes, NAD83 for GNSS". Similarly they have "UTM Zones, NAD83" and "UTM Zones, NAD83 for GNSS"

What is the difference between the "for GNSS" and the other? There should not be any difference. I always use the one that isn't labeled "for GNSS". I did notice that the "Datum type" under coordinate system details is "HPGN" rather than "NAD83". What is an "HPGN" datum? I suppose that HPGN stands for High Precision Geodetic Network or something like that, but it is still the NAD83 datum

Posted : June 25, 2026 6:34 am

john-putnam

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While C3D does not include the 'for GNSS', it does include NAD83 (plain jane); HPGN (HARN) NAD83; NSRS 2007 NAD83; and NSRS 2011 NAD83. I don't see anything difference except the names. It just looks like a way to screw up metadata.

Posted : June 25, 2026 8:20 am

Norman_Oklahoma

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There appears to be no difference at all, at least not for Oregon North. I suspect that the various iterations are there to quiet the minds of GIS types.

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