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I asked this question once before, but I did not receive any feedback on solving on the issue and I am still confused as to what I am doing wrong.

I found a public domain map of Florida counties on Google. All I want to do is add coordinate points from a cvs file to the map. It should be simple, right? Apparently not. I made a cvs file with latitude/ longitude and x,y coordinates, but the points do not line up with the map. Yes, I DID have the same projection for both layers. The counties map had a projection of EPSG 2237, NAD 83/ Florida West (ftUS), so I changed the cvs file to have that same exact projection. I also made negative values for the longitude coordinates for United States. I tried this with various Florida maps to see if the counties map I found was just wrong, but every map I tried had the same issue. I tried various types of x and y coordinates for the points, and nothing was better. This really should be a simple thing to do, so I really would like to know what I'm doing wrong.

  • If the CSV data is lat/lon (aka around x~ -82 and y ~ 26), set the coordinate reference system to 4269 (NAD83), not 2237. You have to get the data added in its "native" coordinate reference system before you can change it. – mkennedy Apr 27 '16 at 0:08
  • What's the coordinate system of the Florida counties map? They don't necessarily have to be the same, just compatible and defined, is the spatial reference of the canvas and both layers defined? Have you enabled project-on-the-fly? gis.stackexchange.com/questions/10087/… – Michael Stimson Apr 27 '16 at 0:12
  • I changed the CRS to NAD 83, and the points still do not line up with the map. Michael, what do you mean by "defined"? Yes, I did enable "project on the fly". – Anne Apr 27 '16 at 2:14
  • Each layer has a coordinate reference system, just the same as the canvas has, it's in the properties tab of each layer. If it's not set, or not set correctly, then there is a chance the points wont line up. Some spatial references are incompatible and can't be transformed on the fly; with QGIS this I've only seen when using a custom coordinate system - the EPSG coded ones should be fine but I've not tested it for all of them. – Michael Stimson Apr 27 '16 at 2:31
  • The CRS on each layer and canvas is set to NAD83 and points still don't line up. – Anne Apr 27 '16 at 2:45
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If the county map is in EPSG:2237, better leave it that way. DO NOT use Set Layer CRS to change it, that will corrupt your data. If you did, change it back. Better use Save As ... for vector data and Raster -> Projections -> Warp for rasters. Both need another filename and a different target CRS.

If you are unsure, set the PROJECT CRS to EPSG:3857, and add an OpenStreetMap background with the QuickMapServices plugin. Then you see which of your layers is correct and which is not.


UPDATE

Your sample points seem to show up at reasonable locations:

enter image description here

  • Hi AndreJ, using the techniques that you said, I was able to figure out that the Counties map is correct and fine, but my CVS file with the points is not correct. Now I'm having a difficult time translating my latitude and longitude points to fit with the map. – Anne Apr 28 '16 at 1:30
  • Degree coordinates should be fine, using EPSG:4326 WGS84 or EPSG:4269 NAD83, but they should be in longitude-latitude order, and decimal degrees instead of degrees-minutes-seconds. Longitudes in the US must be negative. – AndreJ Apr 28 '16 at 5:24
  • The longitude/ latitude/ points still don't match with the map.. even with the projection you suggested. – Anne Apr 29 '16 at 0:57
  • Where did you get the coordinates in the CSV from, and how large is the offset in meters? Can you provide sample coordinates of points that can be recognized in Openstreetmap or Google imagery? – AndreJ Apr 29 '16 at 6:55
  • I got the coordinates from Ebird, they are the sightings of bird observations. I also put the coordinates into Google Earth and the sightings showed up correct in that program. Some sample coordinates are: (28.5821099, -80.6545722). (26.4330582, -80.9416786). (26.3665645, -81.4845986) – Anne May 1 '16 at 1:02

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