A simplified description of the Neptunian magnetic field derived from the Goddard Space Flight Center/Bartol Research Institute I8E1 model which includes internal terms up to and including the octupole (but no external terms) has been used to compute numerically L shell values along the Voyager 2 encounter trajectory and those associated with the N1 through N6 moons and N1R through N6R rings. The complex magnetic field geometry and the rapid rotation of the planet combine to produce an expectation of numerous times when absorption signatures should be observed as a result of the interaction between the trapped particle population and the Neptunian moons and rings. Thus a complete understanding of the observed charged particle fluxes and their variation along the Voyager 2 trajectory must take into account these geometrically anticipated interactions. Similar to Uranus, the large tilt between the dipole term and the rotation axis causes the moons and rings to sweep a very large range of L shells. Furthermore, their orbital motion introduces additional periodicities, causing the maxima and minima in L space to vary systematically with time. The unambiguous association of predicted and observed absorption signatures and times with a particular ring or moon is made very difficult by the superposition of many individual effects. The extremely rapid excursion in L space by Voyager 2 near closest approach, a region most significant for magnetic field models, apparently does not facilitate the unique associations previously used at other planets to provide an independent assessment of the global accuracy of the mathematical models of the field which are inherently nonunique.