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I apologize for posting yet-another-gis-novice's confusion about CRSs, but I have researched the issue and am surprised by what I'm seeing.

In simplest form, I

  • open a new project
  • set On-the-fly (OTF) CRS transformation ON
  • choosing NAD83/Conus Albers (a Projected, and not Geographic CRS) as the Project's CRS (same behavior choosing NAD83/UTM12N)
  • load a 1x1-degree USGS ned30m raster layer which has an assoc. CRS of NAD83 (Geographic CRS)
  • note that the layer comes in "skewed" (a North arrow "decoration" points NNE, about 1-o'clock)
  • note that cursor coordinates appear to be in UTM meters
  • note that the "ruler" distance-measuring tool appears to measure in meters, showing the raster to be approximately 88 x 112 kilometers
  • set raster layer's Layer CRS to NAD83/Conus Albers (to match project's)
  • note that the layer "disappears"
  • note that coordinates of cursor still appear to be UTM meters
  • choose Zoom to that layer
  • note that map is now "squared up" with display (N arrow points N/up)
  • BEFORE moving cursor over map, note that coordinates still appear to be in UTM meters (in "Coordinate:" box at bottom of display)
  • AFTER moving cursor over map, note that the coordinates revert to geographic, Lat and Long
  • after which the "ruler" tool measures the rectangle to be about 1 x 1 (must be degrees again)

As far as I can tell, I have done everything I can to alert QGIS 2.8.6 (similar behavior in 2.14 caused me to try the LTR) to the fact that I prefer meters.

I have also (following other advice I found here) tried Layer->SaveAs (to a Projected CRS), but the resulting 23+GB output hung-up QGIS, causing me to have to abort. (A separate problem owing to my naivete regarding choices I made--or rather, defaults I accepted--in the process of trying to save it.)

This is about as simple an example as I can imagine of wanting, say, to import an elevation file from the USGS and measure the distance around a prominent feature, like a mountain peak, in meters.

Again, I regret my need to broach the subject--again--but I would be deeply appreciative to either find out what I did wrong, or why the behavior I see makes Perfect Sense. Or both.

-- Oertls

Update: The problem is still present in 2.18.23. Project->Properties->CoordDisp is set to MapUnits (automatic), but coords are still displaying in Lat/Long, even though the project CRS is Conus/Albers and the NED layer has been saved-out/reloaded--after relaunching QGIS 2.18--as a Conus/Albers CRS.

However IF I set the NED layer CRS to "NAD83" (its default), coordinates display in meters.

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  • As has been pointed out elsewhere, "defining" how a layer should be displayed, by setting its CRS, is different from "projecting" the layer into a new CRS, which can only be done by "exporting" the layer to a file, specifying the desired CRS, and reloading it. – quagmire Jun 24 '20 at 16:26
  • Furthermore, the problem of a layer "disappearing" may be solved by right-clicking and zooming that layer. – quagmire Jun 24 '20 at 16:27
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In Project -> Project Properties -> General, look out for Coordinate Display.

For some strange reasons, it gets switched to decimal degrees, even when you are working with a projected CRS. It should be set to Map units unless you really want degrees.

You might consider it as bug (http://hub.qgis.org/issues/14319) or a feature...

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