I follow the manual section 7.2.1. Specifying a Projection.
I open a the spearfish mapset and display the raster layer spot.image,
then select Project Properties/Projection and enable OTF.
Click OK and the displayed raster vanishes. I open the
Projection menu and the selected projection is still
the one by default (lonlat) instead of the one of
spot.image (utm). This seems in contradiction with the manual:
way to specify the map projection is to first load a layer with the
projection you want for the entire
map. Then open the Project Properties dialog and click on the Enable on
the fly projection checkbox.
You can now close the Project Properties dialog and add additional
layers to the map."
If I do select the utm settings of spot.image in Project
Properties/Projection, the display seems to work fine.
BTW, if I were displaying now another layer for the same
geographic area but in another projection with OTF enabled, could
I save the layer in the new projection? In other words, can QGis be
used to reproject layers and save them with the new projections?