I wish to make a QGIS project with an orthoimagery layer and a vector layer of GPS points. I'm using QGIS 2.8.2, 64 bit, in Windows 7 on a Lenova t430 laptop. Raster is in EPSG: 32115 (mercator, NAD83, Eastern New York): I add that layer first. When I add a *.gpx layer, which is in EPSG4326 (Lat/Long) WGS84, the points display 1000 km south from where they should be. When I add the layers in the opposite order, the raster layer ends up way up in Canada somewhere. No amount of reprojecting of either layer seems to be helping. Do you have any suggestions?
The best way to find out which layer is correct, is to set the project CRS to EPSG:3857 with
on-the-fly-reprojection enabled, then load a Google or Openstreetmap background via the OpenLayers plugin, then add your layers and check their layer CRS.
Then you see which layer ist placed on the right spot, and which might have a wrong CRS.
BTW this page http://gis.ny.gov/gateway/mg/2014/columbia/#sp notes that the data is in New York State Plane NAD 83 (2011), US Survey Feet , which is EPSG:2260 for Eastern New York. Sometimes QGIS misreads the units on guessing the CRS. You can use
Set CRS for Layer to correct it.