[Qgis-user] How do you see which transform is being used for a given projection?

[John Stevenson - BGS]

Hi,

When I add a layer with OSGB36 (epsg:27700) projection to a project in QGS84 (epsg:4326), I am given an option to select the coordinate transformation to use.  There are multiple options: https://epsg.io/27700.  The best includes a custom correction grid, OSTN15_NTv2.

Once the layer has been added, is there a way to see which transformation was used?

It isn't mentioned in the Coordinate Reference System section of the layer properties.  The definition of OSGB36 in the project projection selection dialog doesn't mention the custom transformation grid.  Is there a way to see it in the project XML?

Thanks,
John
John A Stevenson PhD MSci FGS
Senior Software Developer

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British Geological Survey | The Lyell Centre | Research Avenue South | Edinburgh EH14 4AP | UK

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