Questions tagged [geoid]

The hypothetical, natural, surface of mean sea level for the whole Earth. An equipotential gravitational surface. The datum for orthometric heights.

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Can GDAL Perform Vertical Transformations?

Can GDAL perform vertical transformations? If the answer is yes, please indicate which amongst these listed pages can explain how exactly to accomplish vertical transformations? If there is some ...
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115 views

Adding GDA2020 NTv2 transformation to ArcGIS 10.5

The implementation of GDA2020 is drawing near! In an effort to be ready before time I have downloaded the NTv2 Grid Shift Binary (GSB) transformation grid from ISCM (available here) who are the ...
3
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0answers
85 views

Understanding Google Earth Pro ruler tool algorithms?

When using Google Earth Pro ruler (Tools / Ruler or by clicking on the "ruler" icon), the ruler tool tells us the heading from one point to another which is not the same as that obtained by Karney's ...
2
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0answers
736 views

Correcting incorrect altitudes of points recorded by my Android or how to calculate Geoid Height in QGIS

I tried to edit my question with more details and I also think that lot of people can benefit from this question! I was recording a track with my Android and later I found out that I end up having ...
2
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0answers
414 views

How do you compute vertical transformations in QGIS?

How do you compute vertical transformations in QGIS? Ideally, the procedure / plugin will allow the loading of sundry geoid models.
2
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0answers
413 views

Height of the geoid in ECEF coordinates

I know that the relationship of geoid height N and ellipsoid height h to orthometric height H is defined by H = h - N, but what if I have some position in Earth-Centered-Earth-Fixed (ECEF) coordinates?...
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43 views

What is Considered in Geoid?

I found contradictory sources for what's considered in geoid and can't decide on either side because the sources seem about equally reliable. In particular, the question I'm asking is whether ...
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0answers
91 views

What geoid does WGS 72 use?

I see from the WGS Wikipedia article: Currently, WGS 84 uses the EGM96 (Earth Gravitational Model 1996) geoid, revised in 2004. I see there is an older EGM84 geoid but I couldn't find anything ...
0
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1answer
434 views

Seeking Trimble GGF Geoid File Format Specification?

I want to generate Trimble GGF Geoid files from my software. Can anyone provide me with a format specification for the binary ggf files used by Trimble? I found a basic description on the ...
0
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0answers
431 views

Converting elevation from EU-DEM (ETRS89) to WGS84

I'm having a hard time trying to use elevation data from EU-DEM. This data is in ETRS89 (EPSG:4258), according to their site. Now, when I extract the elevation for a shore, I get 0 meters of ...