In the past few days, the data collectors have noticed that the GPS seems to be 12-13 feet off when they are just walking and shooting in new points.

Question

In the past few days, the data collectors have noticed that the GPS seems to be 12-13 feet off when they are just walking and shooting in new points.  Points were added to an existing layer where they even took a pic where the shot was taken, now we seem to be off to the NW.  We are using Zeno connect and Leica systems.  I've been in contact with both technical supports from who we got them from and Leica, so far, no fix.  Ive made 0 changed to the web maps and have not been able to figure it out.  Any help would be appreciated.

Thanx

X Y Problem.pdf

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JoelCusick1 · Answer

Recommend to occupy "Truth" and resolve the issue of shift (or not) on a control point with coordinates determined by a GNSS survey (likely a surveyor).  This will help you resolve the issue, where comparing to data you showed in your screeenshot can lead you astray, and comes loaded with assumptions your data was in the right place using your workflow.   Use NOAA NGS explorer https://geodesy.noaa.gov/datasheets/ngs_map/ and find a mark near your location with a NAD83(2011) Epoch 2010.0 set of coordinates.  Occupy using your SOP and your location profile and augmentation your receiving from a NTRIP, network connection to Real-Time RTK.  Assuming the vendor who runs the server is also streaming the same Datum of your curated GIS, you can definitevly determine a shift or not.  Its not common that a NTRIP service has switched datums (this will happen eventually), but not on the order of 12'.  But occupying TRUTH is your opportunity to see if your methods and datum shifts in ESRI software is putting your data in the "right" place.

Tooele_City · Answer

After further testing we have figured out that the problem has to do with our base station and the RTK server, still trying to figure what exactly is wrong.