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I am having issues projecting my csv file I have imported in lat/long to our state government-standard projection (EPSG 102121 NAD 1983 Michigan GeoRef (feet)), which is based on Oblique Mercator.

When I pull in the csv, I load the lat/long points, I select 'EPSG 102121- NAD 1983 Michigan GeoRef Feet US' for the "Geometry CRS". When converted to points, the layer misaligns with others in the same projection. My points are still in lat/long, but the other layers have been successfully reprojected to feet.

How do I transform the lat/long points to be reprojected in feet in QGIS? I understand it is still a datum at this point, and that another step is needed, but I guess I assumed since the NAD 1983 MI GeoRef is based on Oblique Mercator, the projection was built in or something.

Is there a step I am missing that requires the geometries of the lat/long to be recalculated in feet? I've only had this issue working with csv files, and it's frustrating.

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    You should always define layers with their actual coordinate reference, not what you want them to be. – Vince May 3 '18 at 12:43
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    If the csv file contains only geographic coordinates (lat/long points), I would venture to guess that it is not EPSG102121. Try setting the projection of the layer you are importing to WGS84 in the layer properties, then save that layer as a shape file changing the projection to EPSG 102121. See if the new shape file overlays properly. If you know the source of the csv file, ask them what projection the data is being provided in. – jbgramm May 3 '18 at 12:47
  • Does anyone know if the issue with MI Georef in QGIS has been resolved? Last updates I see are ~6 yrs old but I haven't been keeping track. QGIS Issue report, StackExchange Question – smiller May 3 '18 at 13:23
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    Thanks, guys. I started QGIS with a blank project, pulled in a TIGER shapefile in an ESPG: 4269 NAD83 datum, pulled in my csv file in the same datum, then saved as points shapefile. Then I opened my main project (with the MI GeoRef 1983 ft set as the default datum), pulled in my points and it aligned perfectly, so I saved as shp in MI Georef. Wanted to include my solution here in the hopes it may help others. – Ashley May 3 '18 at 13:57
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CSV's don't have predefined projection so it is important to know in which projection they were captured. if it is in lat/lon then most probably it is EPSG:4326 (WGS84) projection, or it maybe in ESPG:4269 (NAD83) projection. you have to save the csv in this datum. then on adding layers, qgis will reproject them on the fly .

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Wanted to include my solution here in the hopes it may help others. Rather than adding to confusion by compounding edits on top of edits, I started QGIS fresh with a blank project, pulled in a TIGER shapefile that I knew had an ESPG: 4269 NAD83 datum, pulled in my csv file in the same datum, then saved as points shapefile in ESPG 4269 NAD 1983. Then I opened my main project (with the MI GeoRef 1983 ft set as the default datum), pulled in my points and it aligned perfectly, so I saved as shp in MI Georef.

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