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Wondering if anyone has found a way around this:

I am having issues when importing shp files into Google Earth. I need reasonably accurate measurement data and my measurements change significantly when imported from EPSG 3857 to Google earth (EPSG 4326). I comprehend the difference between the two but am having issues overcoming the problem since my layers have to be based upon locations as projected in the google openlayers plugin, which, to my knowledge, requires EPSG 3857 to be used. Converting the shp file layer projection to EPSG 4326 when saving as a kml has not worked. Neither has changing the layer or project projection in a new project without adding the google openlayers base map.

Alternatively, if there is a time efficient way to set kilometer points along a >500km line in Google Earth without using QGIS I am open ears.

Thanks for looking.

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    None of those systems are very good to measure distances, one because it's in degrees, the other because it has big distortions. I would create the points using a a local EPGS (most countries have official Coordinate systems that minimize the distortions for a particular area), and then project them for display in Google Earth and Open Layers. This way the distance between points in the reality will be for sure more close to 1km. – Alexandre Neto Oct 10 '14 at 10:42
  • I understand that, but for locational accuracy, i.e. the placement of a rivers layer as seen in google earth, I have to use EPSG 3657 because that's what the google openlayers plugin requires. You can't change the CRS of that plugin without some displacement issues coming up or the plugin to just quit on you. For the most part locational accuracy as seen in google earth is the more important aspect of this analysis. Thank you for your input Neto. – eagertolearn Oct 10 '14 at 16:34
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If anyone else has problems with this the best solution I have found is: find the ratio between the measurements in the two projections, divide the desired measurement by the undesired measurement, then multiply the answer by the desired measurement.

For example: The measurement ratio between QGIS EPSG 3857 and Google Earth was 200m:153.15m. I need points on a line (Qchainage plugin) for every kilometer.

200m/153.15m =1.3059094... (1.3059094)(1000m) = 1305.9094m

Use 1305.9094m as your input in QGIS to get ~1000m of output in Google Earth.

I got within .5 meters with this and that's all the accuracy I need fortunately. If anyone finds a better solution please share. Thanks

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