QGIS 1.8.0 on OSX 10.10.5: I've got continent outlines from Natural Earth that are in EPSG:4326 (degrees) plus USGS tree range data in EPSG:2030 (also degrees). When I set the project CRS to EPSG:4326 I get a Mercator projection showing all layers properly. But when I set an equal area projection such as EPSG:2163, the continent outlines vanish; I only see the USGS layers. I'm sure it's something simple I'm missing, but I'm lost!
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I can not reproduce your error with recent versions of QGIS. It might help if you cut the continent outlines to North America before reprojecting them to laea under a different filename, instead of using OTF.– AndreJCommented Apr 10, 2017 at 5:42
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Are you sure you mean 1.8? That's an ancient version and I'd strongly suggest upgrading.– ndawsonCommented Apr 10, 2017 at 8:41
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AndreJ: I've cut all the outlines to NA only - the problem still exists. I can't reproject to equalarea because I have to edit the tree ranges with data that comes in WGS84 degrees.– johnsankeyCommented Apr 10, 2017 at 20:39
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ndawson: the recent upgrade says it only works with OSX 10.9 and before; I tried anyway and it did indeed not work. My son installed an early-2. version; I'll try to get a copy from him to see if that fixes the problem.– johnsankeyCommented Apr 10, 2017 at 20:43
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QGIS 2.0.1 says it won't instal beyond OSX 10.6.8, but when I copied the app into Applications, it runs. However, the problem I encountered with 1.8 remains. Perhaps I should mention that all my prior use of QGIS has been small scale using UTM; this is the first time I've tried a large scale project.– johnsankeyCommented Apr 10, 2017 at 22:13
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OK, I've found out a few things. First, declaring the NAD27 layers as WGS84 to match the continent outlines and keeping OTF off gives visually identical results on continent-wide scale as declaring them as NAD27. Scale 1:250 Second, turning OTF conversion to WGS84 to ON then makes everything vanish: it's because the scale is changed from degrees to meters! As soon as I change the scale from 1:250 to 1:20,000,000 everything shows normally again. Third: when I change the project CRF to US Atlas Equal Area EPSG:2163 with scale 1:20,000,000 OTF shows everything in that projection properly, which is what I wanted all along. So, if I keep OTF off and scale 1:250, I can add my new data to the tree layers in the form I get it. Then by changing scale and turning OTF ON, I get the projection I want. I've no idea how the NAD27 projection seems to work in degrees in both projections when the WGS84 continent outlines don't, but that's a job for the programming guys. I've got a system that works.