[PROJ] Static/Dynamic Webmapping Problem version 2.0

Even Rouault even.rouault at spatialys.com
Wed Jul 17 17:47:34 PDT 2019

On mercredi 17 juillet 2019 17:24:49 CEST Duncan Agnew wrote:
> No, "same point" means "same monument set in the ground". If I understand
> things properly, a measurement in 1994
> (which is analyzed in IRTF and then converted to GDA94) will have some XYZ
> value, call it XYZ94. And a measurement
> in 2020 (analyzed in ITRF and then converted to GDA2020) will have XYZ
> numbers that have the same values as XYZ94.

That doesn't make sense to me. There will be a ~1.8 m shift between the 
coordinates of the same monument expressed in GDA94 and GDA2020 due to plate 
motion between 1994 and 2020. That's the whole point of having GDA2020 
"resynchronized" with ITRF at 2020.00, or I'm missing something...

Spatialys - Geospatial professional services

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