I want to create circles of diameter 20m in QGIS. I create a point and then use vector - geoprocessing tools - fixed distance buffer. My problem is that the size is crazy and worse, the shape is not a circle. My map units are metres and when I use a distance of 0.001 I get an oval 220 m high in north-south direction and 140 m wide in east-west direction.

I am using OSGB 1936 / British National Grid EPSG:27700. I have tried switching to another reference system and back again since in other cases this seems to make QGIS pay attention, but it has not helped in this case.

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    QGIS doesn't care which CRS your project has, it cares about the layer's CRS. Which currently seems to be some geographic CRS. So save your layer in a different, projected CRS, then buffer. – Erik Apr 26 at 12:30
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    0.001 degrees of longitude varies from ~111m near the Equator to ~0m near the poles. A geodetic buffer takes this into account, generating visibly egg-shaped objects in high latitudes. – Vince Apr 26 at 12:46
  • Erik - thats it. Making sure the layer with the points in uses British National Grid solves the problem. Thanks very much. Steve – Steve Bolsover Apr 26 at 17:11

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