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I'm trying to load some DRG data from the USGS into QGIS. The source data uses UTM coordinate and I can't seem to get it to overlay with WGS 84 vector data. I (think) I've followed the recommended procedure to transform the coordinates but obviously I'm doing something wrong.

I'm loading the .jpg file and assume the associated .jgw file is loading with it. QGIS reports translating the CRS to WGS 84 (project default) when I load it. When I move the mouse over the image the coordinates look like utm values in the range from the world file and of course the data does not overlay with my vector data.

The data did not come with a .crs file.

I'm a new QGIS user.

World file contents:

1.464843750000
0.000000000000
0.000000000000
-1.464843750000
412500.732421875000
4190999.267578125000
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Since the picture's world file has meters as units, WGS84 is definitely wrong. You have to find out which UTM zone your data is in, then use Rightclick -> Set CRS for Layer to correct the wrong CRS.

BTW, jpg files never come with a .crs file. You have to enter the CRS manually. Once done, you can save to Geotiff which has the CRS information stored inside the file.

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I did some further research and ended up with a custom CRS file as @AndreJ suggested and that solved the problem. Contents of the CRS for this case:

+proj=utm +lat_0=32 +lat_2=40 +lon_0=-78 +lon_1=-75 +lon_2=-72 +datum=WGS84 +units=m +no_defs
  • UTM projection normally does not use lat_2, lon_1 and lon_2 parameters. – AndreJ Jul 2 '15 at 15:31
  • Hi Andre - I would think that UTM needs to know the central meridian longitude from somewhere. In any case I have since learned that the EPSG:32617 does the job for me so no need for custom CRS. – Hank Brandenburg Jul 2 '15 at 18:12
  • +zone=17 identifies the central meridian, counting from -177°E eastwards in 6-degree-steps. +south is added for CRS below the equator. – AndreJ Jul 2 '15 at 18:23
  • Thanks Andre - the zone definitely makes sense to me now! – Hank Brandenburg Jul 4 '15 at 1:46

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