An optical system includes a plurality of internal apertures, a plurality of external optical assemblies and a telescope assembly positioned between the plurality of internal apertures and the plurality of external optical assemblies. Each internal aperture is operable to receive a corresponding aperture-specific optical signal. Each external optical assembly corresponds to one of the internal apertures, and each external optical assembly is operable to direct the aperture-specific optical signal of the corresponding internal aperture in a corresponding external direction. The external direction for each external optical assembly is independently controllable and the telescope assembly defines a shared optical train arranged to direct the aperture-specific optical signals between each internal aperture and the corresponding external optical assembly.