Lens Lab
    Sigma MF 28-84 mm f/ 3.5-4.5 MC Zoom Theta III
    Sigma MF 28-84 mm f/ 3.5-4.5 MC Zoom Theta III

    Sigma MF 28-84 mm f/ 3.5-4.5 MC Zoom Theta III

    28–85mm · f/3.5–4.5

    Overview

    The Sigma MF 28-84 mm f/3.5-4.5 MC Zoom Theta III is a vintage manual-focus zoom with all-metal build and rubberized grips, though the zoom ring is small and zoom creep is present. Its variable aperture requires adjusting the aperture ring when zooming to unlock the full range, which can be cumbersome. Optical quality is decent but typical of its era; a coating bubble was noted on one sample but did not affect images. It suits film photographers seeking a versatile walk-around lens, but modern users may find handling and aperture limitations frustrating.