1

I'm trying to georeference an aerial image of a site over it's exact coordinates using WGS 84. The same coordinate reference system is used on the settings. I'm not sure what to do from here, is there something I'm doing wrong? And just to add, I have tried the original image in both JPEG and TIFF. Both end up saving as GeoTIFF's and there's no other option in that regard.

Map Window (After Georeferencing) Georeferencer Window [View of Georeferenced Points on Map][3 View of Georeferencer Settings

2

For georeferencing, you are supposed to grab four points within the image, and supply the coordinates in the target CRS.

As far as I see, you have entered the same coordinates dstX and dstY for all points. That will not work.

Apart from that, I see a positive value for dstX in the last row of the second screenshot (but not in the last). That might be wrong too.


Furthermore, the source raster should be in RGB, not paletted colours. You can transform that with Gimp, or inside QGIS with Raster -> Conversion -> PCT to RGB ....

  • I'm not sure what is with the second image, there are supposed to be negative numbers where other negative numbers are present. And with the same coordinates, it appears that the Georeferencer is trimming down the destination coordinates (and most likely the source coordinates as well). An example would be the dstY for one point, instead of 38.29, it should be 38.2946659. I made the change manually, but the moment I clicked outside of the box, it cut back down to 38.29. So I'm stuck again (but I'm sure your thoughts would work in a normal situation). – Matthew Oct 16 '15 at 4:26
  • It might help to convert the degrees to UTM or your State Plane Coordinate System in meters or feet. You have to change the target CRS accordingly. Or you can georeference against Google imagery with the Openlayers plugin, using EPSG:3857. Does the extent of the black rectangle match the extent of the image? – AndreJ Oct 16 '15 at 5:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.