3 aspherical of which 1 hybrid, 3 extra low dispersion
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This lens is (at least to me) one of the most exciting options available in the EF-M mount. [...] It has a very nice build quality, well-functioning manual controls, and has exceptional image quality even wide open. It’s a great focal length, has great color rendition, and is a lot of fun to use. [...] It’s greatest asset is a fully usable f/2 aperture that is 2+ stops faster than the Canon zoom.