Apochromat APO Design (Invisible CA): The Laowa 100mm f/2.8 has an Apochromat (APO) design where the chromatic aberration (CA) at BOTH in-focus and out-of-focus areas (Longitudinal CA) is controlled to the minimal Features: This 100mm lens can cover full-frame sensor size and focus from 2:1 magnification to infinity. The lens has a similar physical size to other 100mm Macro lenses in the market but its wider magnification range allows macro photographers to capture subjects of any size 2:1 Magnification: Laowa 100mm f/2.8 2:1 Ultra-Macro is the second 2:1 Macro lens that we have (The first one is the 60mm f/2.8). The 100mm is one of the most common focal length for macro photography usage. All of the 100mm macro lenses in the market can only reproduce 1:1 magnification (life-size) image only. The extended 2x magnification means more details can be seen through the lens