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I've been trying to georeference a raster.The ground control points I choose using 'from map canvas' are quite close to the original points, but the results are far far away and distorted. Could anyone help with it? The screenshots are below: 1. After choosing GCPs and setting up transformation parameters, you can see the red lines indicating the to-be-moved-to positions: enter image description here

  1. the GCPs in QGIS:

![enter image description here

  1. The result raster is distorted and far far away from original location: enter image description here
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  • What are you transformation parameters? I get the best result using the Helmert transformation.
    – Jakob
    Mar 11 '20 at 11:43
  • I used linear, but I don't think it's the problem. No matter linear or hermert, it should be shifted so far away.
    – Summer
    Mar 11 '20 at 11:47
  • I wonder if the georeferencer is dropping decimals. Now all the GCPs seem to be very close to each other, many even at exactly same coordinates. I would try to give the ground control points in some metric coordinates instead of degrees.
    – user30184
    Mar 11 '20 at 12:08
  • Use a different CRS.
    – Erik
    Mar 11 '20 at 12:35
  • Will try a different CRS
    – Summer
    Mar 11 '20 at 12:39

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