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Can anyone tell me the steps to display my village map (as a tif/tfw pair of files) over an OSM raster layer (from the OpenLayers plugin) in QGIS? Because every time I try my village ends up in the middle of the ocean south of Lagos!

I know that questions like this have been asked before, and I have looked at several answers and tried to follow what they said, but so far without success. I have looked at the documentation. I understand from EPSG 3857 or 4326 for GoogleMaps, OpenStreetMap and Leaflet there are complications. One of the articles I have tried to follow (also unsuccessfully) is at http://maps.cga.harvard.edu/qgis/wkshop/basemap.php.

The tfw file is:

0.6351247107
0.0000000000
0.0000000000
-0.6350766811
532808.8175623553
273200.4324616595

I have tried combinations of:

  • loading the tif file with CRS EPSG:4326 and EPSG:3857
  • switching on and off 'on the fly' CRS transformation
  • changing the project CRS to EPSG:4326 and EPSG:3857
  • warp (reprojecting) my village file with source CRS EPSG:3857 and target CRS EPSG:4326, and then using the resulting tif file
  • switching between degrees and metres

I am usually good at following instructions, but this has me beaten. I thought I understood a little about about projections, but the more I read and what I try does not work, the more I am confused.

What are the steps I should take?

2

After lots more investigations and thought, I realised that my village map uses the British National Grid (EPSG:27700), and using that solved all the problems.

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