Problem observed in QGIS 3.22 on a Mac.

I am teaching a university GIS course and we try to support QGIS users on both Mac and PC, but I do not personally have a Mac. I am also more used to ArcMap. This issue was reported by multiple students so please forgive me if it takes some time to respond to any suggestions that are made, as I will need to pass them on and wait for someone to report back.

I have provided data to students for an exercise, in CRS British National Grid (EPSG 27700), including shapefiles and raster datasets (.tif with .tfw). All have the same extent (30 x 30 km) and resolution (25m). Data were exported as .shp and .tif from ArcMap 10.6.1. For some Mac QGIS users, the shapefiles display in the correct location but the rasters do not. The upper left / NW corner coincides but the data extends 60km E and S from that. This suggests the pixel size is being interpreted wrongly, but the raster layer's Properties in QGIS report the correct location, extent, pixel size and number of rows and columns.

What is happening here and how can we fix it?

Some others on Macs have reported the same issue, with different data packs (always the tif+tfw is too large and extends SE, always so far in EPSG 27700). Other Mac users see the data without issue, and I do have no problems on v3.16 on Windows. (When we began the course v 3.16 was the long-term stable release and is provided on my university PC.)

Orange square is correct extent, raster should match exactly Raster layer properties showing correct/expected extent and cell size Reference shapefile (orange square) properties showing expected extent and cell size


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