An optical system includes an optical element and an optical filter with a first set of channels and a second set of channels respectively associated with a first region and a second region of the optical filter. The optical element causes first light beams and second light beams associated with a subject to respectively fall incident on the first region within a first incidence angle range and on the second region within a second incidence angle range. A first channel, of the first set of channels, passes, based on the first incidence angle range, a set of the first light beams that are associated with a first subrange of a particular wavelength range. A second channel, of the second set of channels, passes, based on the second incidence angle range, a set of the second light beams that are associated with a second subrange of the particular wavelength range.