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I'm using Qgis Dufour 2.0.1 and the Openlayers Plugin for images.

I'm working on a golf course project where everyone thinks in yards. I've tried different CRS (now working the State Plane Missouri East in FEET). The measure tool units match this CRS EPSG 102696.

Is there a simple way to change the CRS code so that measurements will be in Yards rather than in US-feet?

  • 1
    Welcome to GIS SE, your question title and your question within your question are contradicting each other, please clarify. – artwork21 Jun 19 '14 at 18:01
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PROJCS["NAD_1983_StatePlane_Missouri_East_FIPS_2401_Feet",
GEOGCS["GCS_North_American_1983",
    DATUM["North_American_Datum_1983",
        SPHEROID["GRS_1980",6378137,298.257222101]],
    PRIMEM["Greenwich",0],
    UNIT["Degree",0.017453292519943295]],
PROJECTION["Transverse_Mercator"],
PARAMETER["False_Easting",820208.3333333333],
PARAMETER["False_Northing",0],
PARAMETER["Central_Meridian",-90.5],
PARAMETER["Scale_Factor",0.9999333333333333],
PARAMETER["Latitude_Of_Origin",35.83333333333334],
UNIT["Foot_US",0.30480060960121924],
AUTHORITY["EPSG","102696"]]

This is what I am seeing from spatialreference.org. It looks like the unit of this projection is in feet, which means that your measure tool, buffer, distance tools, etc., will also use this unit.

The easiest answer, as I see it, would be to make a custom projection based on this one that uses yards instead of feet. I was able to find this blog post about someone customizing a WKT projection to use meters instead of feet, which hopefully you might be able to emulate.

  • This gives me a place to search. It appears the blog post uses a different format "WKL" rather than the format I have seen in QGIS Here's the format for Missouri State Plane in Feet +proj=tmerc +lat_0=35.83333333333334 +lon_0=-90.5 +k=0.9999333333333333 +x_0=250000 +y_0=0 +datum=NAD83 +units=us-ft +no_defs – GeoV Jun 20 '14 at 3:45
  • Mistake: I meant "WKT" format. – GeoV Jun 20 '14 at 3:58
  • I think I found the format at at spatialreference.org/ref/esri/102696.... ...Looks like teh "Proj4" format is used in Qgis Now how do I do convert the changes that MakinFlippFloppy's blog post describes (in WKT format) to Proj2?? – GeoV Jun 20 '14 at 4:10
  • Write the WKT definition into a text file 102696yd.prj, then run gdalsrsinfo 102696yd.prj > out.txt in OSGEO4W shell to get the proj definition string. With that you can create a custom CRS. It might be necessary to change the false easting to yards too, and units other than metres and feet might need GDAL 1.11. – AndreJ Jun 20 '14 at 5:59
  • Still new at this forum so forgive poor my ignorance of things like "mini-Markdown" formatting. However, @Andre's comments were helpful. downloaded OSGEO4W and used the gdalsrsinfo command to convert to PROJ.4 format. BUT still can't get map units in yards. I'm beginning to think I'm overcomplicating this. Guess I will just have to write down the distance measured and multiply by 3. Seems like Qgis measure tool would allow different units? – GeoV Jun 20 '14 at 21:09
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The support for correct non-meter/feet units handling was added in GDAL with version 1.11, see

http://hub.qgis.org/issues/9414

http://trac.osgeo.org/gdal/ticket/5370

Your QGIS Dufour is still running with GDAL 1.10, so you are out of luck with that.

BUT the new QGIS 2.4 is just around the corner, and I hope it will work with all available units. You will have to set something like +units=us-yd in your proj string.

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