rms. The results depend on the SPICE kernels used as
      input, the compiler and supporting libraries, and the machine
      specific arithmetic implementation.
 
      1) Suppose that MGS has taken a picture of Mars at time `etrec' with
         the MOC narrow angle camera. We want to know the latitude and
         longitude associated with two pixels projected to Mars'
         surface: the boresight and one along the boundary of the
         field of view (FOV). Due to light time, the photons taken in
