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<span style="mso-fareast-language:EN-US" lang="EN-GB"><o:p></o:p></span>
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<p class="MsoNormal"><span style="mso-fareast-language:EN-US"
lang="EN-GB"><o:p> </o:p>To prevent users to make different
choices in similar use cases, the documentation should
indicate what to do for Lowest Astronomical Tide (LAT) or
other Chart Datum grids.</span></p>
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Cf <a class="moz-txt-link-freetext" href="https://github.com/OSGeo/PROJ/pull/3668">https://github.com/OSGeo/PROJ/pull/3668</a> +
<a class="moz-txt-link-freetext" href="https://github.com/OSGeo/PROJ-data/pull/97">https://github.com/OSGeo/PROJ-data/pull/97</a><br>
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<p class="MsoNormal"><span style="mso-fareast-language:EN-US"
lang="EN-GB"><o:p></o:p></span></p>
<span lang="EN-GB"><o:p> </o:p></span>
<p class="MsoNormal"><span lang="EN-GB">Another question is if
it is a good idea to add a Geodetic TIFF Grid for the
transformation between the national levelling height system
NAP and LAT of the Netherlands to EPSG? And should we add
that instead of the ETRS89 – LAT transformation, or should
we publish both in EPSG to shorten the number of
transformation steps in PROJ?
</span></p>
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<p>It is really up to you, the use cases you want to solve and also
depending on if EPSG has a policy regarding this. PROJ can
automatically chain 2 GeogCRS->VertCRS transformation where the
GeogCRS is the same (e.g doing EGM96 -> EGM2008, and I believe
it can also chain a GeogCRS->VertCRS and VertCRS->VertCRS
with a pivot common VertCRS. That said explicit concatenated
transformations in the registry can help it.</p>
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<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.spatialys.com">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
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