Neptune beam maps produced by:
1) Building the map of observations with Neptune
   including correction for the drift of Neptune.
   (neptune*fits)
2) Building the 'shadow' map of observations of the
  same field -without- neptune, but including the same
  drift as in 1.
  (shadow*fits)
3) Subtracting 0.85 * the shadow map from the Neptune map
   (empirically determined factor).
4) Correcting the pixel sizes to a) the color or the CIB
   b) the fact that Neptune is slightly extended.  The latter
   is modeled assuming a constant brightness disc.  The two
   corrections are very small and almost cancel each other out.
5) Renormalizing the peak following 5.44 in the SPIRE observers
   manual.
The final products are beam*fits.