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I'm trying to load into the QGIS an image generated from the NA CIA Fact Book PDF which uses Lambert Conformal Conic Projection, standard parallels 25°N and 77°N. I'd like to work with the exact projection from this PDF and overlay some vector data on top of it.

I think there is something wrong in my workflow. Here is what I've done so far

  1. export the PDF to a TIFF file
  2. Define a Custom CRS in QGIS:

+proj=lcc +lat_1=25 +lat_2=77 +lat_0=40 +lon_0=-96 +x_0=0 +y_0=0 +datum=NAD83 +units=m +no_defs

  1. Open the tiff file in georeferencer. When prompted for CRS, pick the custom defined lcc as above

  2. Add 6 or so GCP at the grid intersections

  3. Transformation settings: Linear/Nearest Neighbor/Target SRS: select the custom defined as above.
  4. Once the image loads into qgis it does not look correct. I've tried Polynomial 2 transform but that didn't fix either.

My understanding is that when the source and dest projection does not change I should be able to use the Liniar transformation.

using QGIS 2.18.

enter image description here

result in qgis: enter image description here

  • 1
    lon_0 of the map seems to be west of the 100° meridian. – AndreJ Nov 11 '17 at 17:17
  • i missed that, thanks. corrected to -101.64. What does lat_0 refer to? may that is wrong as well? – k3it Nov 11 '17 at 20:13
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    You're georeferencing to lat/lon, not to LCC. Convert the lat/lon values to the projected CRS you want to use, then georeference the image. – mkennedy Nov 12 '17 at 1:33

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