I'm rotating my vectors by the quaternion rotation.
each vector is made by (objectVector – camVector)
I included your codebox into mine and put the azimuth & elevation calculation in another codebox.
I don't know if it is a problem of vector normalization or whatever, but it still doesn't work.
if I move the camera "around" the object, by keeping the object in the center of my view, I should still have az=0 & el=0 … this is basic and I absolutely don't understand why I don't have that :-(