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I'm georeferencing a bunch of maps in ArcMap 10.0. The Shift and Rotate commands are pretty easy to use, no problems there. But whenever I use the Scale command, the image completely changes position. Is there a way to put an anchor down (similar to the rotate tool)? I feel like I must be missing something but haven't figured out what it is yet. I don't want to rubbersheet them into place, so I'm trying not to use control points until I have it in position, but first I need to make sure the scale bar on the map matches the distance it's supposed to.

Edit: Asking a question does wonders in finding an answer, even when nobody has answered yet. I found the Rescale_management tool and will use that to set the scale properly first, then position. If the length of the scale bar is 1256ft and it should be 1200ft, I'll use a factor of .9554 in the X and the Y directions. Is there a better way?

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    Just to throw my hat in the ring... I never use the scale tools. I use control points exclusively. Granted, I'm usually doing a quick georef just to get an idea of where something is, or do a quick-and-dirty digitization of a project area for a map in a proposal or bid. I've never had any issues, even with maps that are rotated strangely or at a weird scale. I just make sure that the points I'm using are reliable and I try to distribute them across the image. That's my two cents.
    – Kevin
    Feb 20, 2013 at 16:48
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    I agree with @Kevin that georeferencing is best accomplished using ground control points and the georeferencing toolbar. Rotate, shift and scale within the georeferencing toolbar are usually done before adding links.
    – Aaron ♦
    Feb 20, 2013 at 17:07
  • Is there a way to use control points, but force the map to NOT change shape? Basically using the control points to only Scale, Shift and Rotate the map?
    – cndnflyr
    Feb 20, 2013 at 18:59
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    Put in a control point with Auto Adjust turned off and just stack it. Select a zero-order polynomial transformation. Then hit rectify and see what the copy looks like. With just one stacked control point, it shouldn't skew your raster at all. It's also interesting to note that the first 3 control points only align, rotate, and scale without skewing (at least in my experience ;)).
    – Baltok
    Feb 20, 2013 at 19:56
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    If you're georeferencing something just based on the graphical scale bar, you can just create a temporary line feature in a shapefile with the same length as your scale bar and georeference to that using control points.
    – Dan C
    Feb 25, 2013 at 14:40

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