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The total magnification due to a point lens has been of particular interestas the theorem that gravitational lensing results in light amplification forall observers appears to contradict the conservation of photon number. This hasbeen discussed several times, and various resolutions have been offered. Inthis note, we use a kinematic approach to provide a formula for themagnification factor for the primary image accurate to first order and validfor rays leaving the source at any trajectory. We thus determine themagnification over a sphere surrounding the system. A new result found is thatwhile the magnification dips below unity far from the optical axis as noted byothers, it returns to unity directly behind the source.

A Note on the Overall Magnification of a Gravitational Point-Source-Point-Lens System