[Qgis-user] Simple Georeference a .png chart

[AntonioLocandro]

Hi, I georeferenced it and the chart is indeed to scale, a few pointers here

1. When you georeference the control points and propose a transformation you
will get a residual, you usually aim for a low value less than 1 pixel for
example, the more accurate you select the crosshairs the more accurate the
georeferencing.

2. The chart will be rotated because the chart isn't aligned North, nothing
you can do about that, aviation charts usually companies like Navtech,
Jeppesen and Lido (as shown) will do this in order to be able to show the
area zoomed. I have attached the georeferenced image against Bing Aerial
overlay and you can see they kind of match

What is your goal in georeferencing this data?

<http://osgeo-org.1560.x6.nabble.com/file/n5167728/chart.png> 



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