1. An imaging system, comprising: a support frame; four image sensors carried by the support frame; each image sensor comprising a lens system having an optical axis and a focal plane array aligned with the optical axis of the lens system; each image sensor having a field of view that is at least substantially coterminous with the field of view of each adjacent image sensor; the image sensors arranged so that: the optical axis of each lens system is substantially collinear with a median of a common notional regular tetrahedron; each focal plane array is positioned between the lens system of its respective image sensor and a centroid of the notional tetrahedron; and each image sensor faces outwardly relative to the centroid of the notional tetrahedron.