Hello,
I have create a custom geographic transformation for my project. I want to use this transform data on the fly in my map in ArcGIS Pro, so I can view multiple dataset in different co-ordinate systems together. Some of these cannot be reproejcted, such as the WMS layer from the British Geological Society (BGS) Borehole Database.
I have these layers:
- BGS Borehole WMS layer - British National Grid (In the form of a projected coord system OSGB_1936)
- historical borehole data for project - project specific projected coordinate system (Created by a company called SnakeGrid. The project specific projected coord system is called TPEN11-TM, and has an accompanying geographic coord system called TPEN11-IRF.
I have created a custom transformation using the ArcGIS tool (and using the TPEN11-TM.prj, TPEN11-IRF and NTv2 .gsb files provided by Snakegrid for this project). This transformation is for converting between geographic system GCS_ETRS89 to the geographic system TPEN11_IRF. The ArcGIS Pro built-in transformers can then convert the data from ETRS89 tto OSGB 1936 (using OTSN02 NTv2 .gsb).
ArcGIS recognises the custom transformation I have created, see attached screenshot (select_transformation.png). The name of the custom transformation is 'TN15-ETRS89-to-TPEN11-IRF'. ArGIS Pro the adds '+OSGB 1936 to ETRS_1989_1' to convert it the rest of the way. However the problem is that once I click 'ok' to close the box it will not apply this transformation on my map. My data on the map doesn't transform and is not displaying together. When I re-open the map transformations list, the list is still at 'none'. See attached screenshot 'none_selected'. This is very frustrating.
To cut a long story short, Has anyone else come across this problem of ArcGIS Pro not applying a custom transformation that is clearly being recognised in the list by ArcGIS Pro and is selectable? Any ideas why it won't apply?
On a semi-related note, the custom transformation works perfectly to project data. I have been successful in using the 'project' tool to use my custom transformation to convert data from British National Grid into my project specific co-ordinate system (see image 'project_transformer.png' So there is clearly nothing wrong with the accuracy of the custom transformation, it's working perfectly using the 'project' tool, it just won't be applied by ArcGIS Pro for on-the-fly transformation (which is what I badly need).
I'm using ArcGIS Pro 2.7
