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<FONT FACE="Verdana"><SPAN STYLE='font-size:12.0px'>I have a historic map that I georeferenced using i.rectify. To help me compare features to modern maps, I have overlaid a 1’ lon/lat grid.<BR>
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I would like to display the undistorted original XY map with the lon/lat grid back-projected on top to show the geometric distortion. In other words, I want the originally straight lines of the grid displayed as curves based on the reverse of the i.rectify transformation.<BR>
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Is there any way to extract the transform parameters and use them to reverse the i.rectify transformation? Are there other ways to accomplish something similar?<BR>
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Thanks,<BR>
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-Dwight</SPAN></FONT>
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