1. An optical system, comprising: a first optical component having a first optical axis and providing a first field of view; a second optical component having a second optical axis and providing a second field of view; an imaging system having an imaging axis; and a housing for mounting the first and second optical components, the housing configured to rotate about a rotation axis to a first position wherein the first optical axis is at least substantially coincident with the imaging axis, and to a second position wherein the second optical axis is at least substantially coincident with the imaging axis; wherein the rotation axis is at least substantially perpendicular to the imaging axis.