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Output Coordinate System - Vertical Datum Option

Hello,

What would be the most accurate vertical datum to use when outputting point clouds to the coordinate system MT83-IF (epsg 2256)? Typically we choose EGM96 but only because it is the default selected. Is there a better option?

Thanks,

Hey there,

There are plenty of local geoid models for the US you can choose from. You can check out this database: https://www.ngs.noaa.gov/GEOID/.

If the database above did not help, you should directly contact the local mapping institute, which can provide more information about the most appropriate vertical datum. When you select a different vertical datum than what you find in Pix4Dmapper, then you should provide the offset between the desired datum and the ellipsoid of the selected horizontal coordinate system. There is a bit of maths behind this calculation, because you should know (or compute) the shift/offset between the current vertical coordinate system and the target coordinate system. This shift can be added in the Geoid Height Above XXX Ellipsoid option. You can find more information about when to use the Geoid Above the Ellipsoid Function here: https://support.pix4d.com/hc/en-us/articles/211739726-When-to-use-the-Geoid-Height-Above-the-Ellipsoid-Function

Cheers,

Teodora

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