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(Spatial) data harmonisation with hale»studio (formerly HUMBOLDT Alignment Editor)
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Remove discussion of datum parameters from the Unable to determine CRS dialog #760

Closed Kate-Lyndegaard closed 3 weeks ago

Kate-Lyndegaard commented 4 years ago

I think we should update the text highlighted in red which appears in the Unable to determine CRS dialog for several reasons.

First, I feel that the discussion of datum parameters should occur when it has been determined that a datum transformation is required. I think that the issue of datum transformations would be better handled in the Coordinate Reference System dialogs, or in a project setting which would allow the use to enter the details.

Second, the TOWGS84 parameter is now deprecated and it is not a "one-size-fits-all" datum transformation. The new WKT specification states:

TOWGS84 is a form of abridged coordinate transformation (see 20.2.1) but inappropriately modelled as part of a geodetic datum definition (a geodetic datum definition should not include a relationship to WGS 84). This document has no backward compatibility with the TOWGS84 object.

Bursa Wolf is just one among several coordinate transformation methods: https://www.epsg-registry.org/export.htm?gml=urn:ogc:def:method:EPSG::1033 (substitute the last four digits to find the coordinate transformation method you are looking for, 1033 is Bursa Wolf). I think we should prepare to allow users to supply coordinate transformation methods as outlined in the latest WKT specification. The methods can be found in the EPSG Geodetic Parameter Dataset at the link above.

Thirdly, GIS software typically provides a warning alongside information about the loss of data accuracy when a datum transformation is performed. I think this gets lost in the current message (along with the option to specify transformation parameters).

If we require the user to provide an EPSG code in order to apply a CRS definition, I don't think we should confuse this with datum transformation parameters.

github-actions[bot] commented 3 months ago

This issue has been automatically marked as stale because it has not had activity in the last 60 days. It will be closed in two weeks if no further activity occurs. Thank you for your contributions.

github-actions[bot] commented 1 month ago

This issue has been automatically marked as stale because it has not had activity in the last 60 days. It will be closed in two weeks if no further activity occurs. Thank you for your contributions.

github-actions[bot] commented 3 weeks ago

This issue has been automatically closed due to inactivity. If it is still valid, please post a comment.