Olympus's extraordinary constant-aperture superzoom with IS, covering 24-200mm equivalent.
The Olympus M.Zuiko Digital ED 12-100mm f/4 IS PRO was released in 2016 as Olympus's highest-specification general-purpose zoom for the Micro Four Thirds system, providing an 24-200mm full-frame equivalent range with constant f/4 aperture and built-in optical IS. The lens IS cooperates with body IBIS through Dual IS 2 on compatible Olympus and Panasonic bodies for combined stabilisation up to 6.5 stops. Weather and dust sealing is built in throughout.
The optical design uses 17 elements in 11 groups. Seven circular aperture blades produce smooth bokeh. The 72mm filter thread requires a large-format filter set. At 561g the lens is the heaviest MFT standard zoom, reflecting the constant f/4 aperture and optical IS throughout the 24-200mm equivalent range. Minimum focus distance of 0.15m at the wide end enables close-up shooting. Lens IS cooperates with body IBIS for Dual IS 2. Weather and dust sealing requires pairing with a sealed OM-D body for full weather resistance. Constant f/4 aperture throughout.
The 24-200mm equivalent range in a single weather-sealed f/4 zoom is the 12-100mm f/4 PRO's defining practical characteristic — covering the vast majority of general photography focal lengths without a lens change. The Dual IS 2 combination of lens IS and body IBIS provides up to 6.5 stops of combined compensation, enabling handheld telephoto use in challenging conditions. The constant f/4 aperture through a 200mm equivalent range in a weather-sealed lens is a combination not achievable in any other mirrorless system at comparable weight.
On the used market the M.Zuiko 12-100mm f/4 IS PRO commands a premium among MFT lenses, reflecting its broad utility and PRO weather-sealing. Condition checks: lens IS and Dual IS 2 cooperation with compatible bodies, weather sealing at the zoom barrel, and front element for marks. The 72mm filter thread requires a dedicated large-format set. The Olympus M.Zuiko 12-40mm f/2.8 PRO provides f/2.8 at a shorter range. Compatible with all Micro Four Thirds bodies; Dual IS 2 requires compatible Olympus/OM System or Panasonic bodies.