Which geoid should I use for north germany?

Reach RX RTK configuration
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I am using the Emlid Reach rx in north germany (Soltau, Niedersachsen) and am getting incorrect heights. The Geoid is currently the DHHS20216 but I am pretty sure I am using the wrong one. My height data is 10 cm too low.

Which geoid should I be using for height above sea level?

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First question. Which correction source do you use?
If it is not SAPOS, AXIO, EUREF or any other reliable and controlled provider, it is highly likely that the data you receive is faulty.
(EPSG 25832 and GCG2016 is the correct setting for Flow.)

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By the way…GCG2016 is not in my list of geoids in Emlid flow.Do I have to import it somehow?

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Hi. I am using the Sapos service from LGLN.
Yours,
Robert

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Hi @r.buckley,

The Geoid is currently the DHHS20216 but I am pretty sure I am using the wrong one. My height data is 10 cm too low.

Where did you get the height data that you compared with your RX measurements? Is it from one of the state geodetic controls?

By the way…GCG2016 is not in my list of geoids in Emlid flow.Do I have to import it somehow?

GCG2016 is the geoid used to transform the heights from ellipsoid to DHHN2016 height. So you should be good to go.

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I have configured everything as shown in the screenshot.

Bildschirmfoto 2024-06-13 um 16.32.44
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The height accuracy of the point was very good. However the GPS was 1M too far east and nearly 4 meters to far south.

I was expecting cm accuracy with the easting and northings so i’m wondering what is wrong now. I had over 30 satellites and a green light on the reach rx.

Any hints?

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Can you share your data with us, along with the known points against which you’re comparing your measurements? It’s possible that the wrong datum and projection were used and that the known points are in different CS than the measurements.

Since it contains sensitive information, you can email us at support@emlid.com. Thank you!

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We were able to sort the problem out.

The orthometric height can only be found in the ‘Survey’ section close to the values for Easting and Northing.

The ‘undulation’ was the perceived difference between the DHHN2016 height and the WGS84 ellipsoidal height.

Regards

Buddy