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I am trying to georeference a newly acquired satellite image to a previously georeferenced image, i.e. match the newer raster to the older one with manually or automatically created control points. I'm trying to work out whether these control points are created by first selecting a point on the georeferenced raster (or vector), then the corresponding point on the unreferenced raster, or is it the other way around. Or when I automatically generate points, which are the red and green crosses?

There is little detail in the help pages for ArcGIS. The most info I can find is this (my emphasis):

The connection between one control point on the raster dataset (the from point) and the corresponding control point on the aligned target data (the to point) is a link.

The example below shows a from control point (yellow cross) placed on the vector target data at a street crossing and the associated control point (green cross) placed on the raster dataset. enter image description here

Source: Fundamentals of georeferencing a raster dataset

Is it just me or are those definitions of the from and to points contradictory? What is correct?

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    from: new/ungeoreferenced data; to: the data or coordinates that you want it to be georeferenced to. In the photo, the yellow cross (from) is offset from the freeway where it should be (to).
    – mkennedy
    Commented Mar 26, 2018 at 22:42
  • @mkennedy So in the graphic example, the vector layer is being georefenced to the raster? That would explain my confusion, I was expecting the raster to be georeferenced to the vector (the more usual scenario).
    – nicfit
    Commented Mar 26, 2018 at 23:19
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    @nicfit, I agree with your comment about the confusion in the ESRI example, it does appear to be georeferencing the vector to the raster (contrary to the title of the article). mkennedy comment is correct though.
    – Dan
    Commented Mar 26, 2018 at 23:41
  • @nicfit, your original assumption is correct. You want to move the raster to the vector. So the green cross should move to the yellow cross. So, click where the green cross is and then where the yellow cross.
    – Fezter
    Commented Mar 26, 2018 at 23:43
  • I think the "a from control point" text is wrong because it goes on to say "vector target data". I think "from" should be removed. So the green cross is the 'from' control point while the yellow cross is the 'to' control point.
    – mkennedy
    Commented Mar 27, 2018 at 17:33

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