The Samyang 24mm f 1.4 ED AS IF UMC Lens is a wide-angle lens perfect for landscape, travel & documentary photography. The Samyang 24mm f/1.4 is a manual focus lens constructed of 13 lenses (including 4 ED glass elements) arranged in 12 groups, with multi-layered & anti-reflective UMC coatings to help prevent ghosting & flare & to ensure a high-contrast image. Thanks to its fast f 1.4 maximum aperture, the Samyang 24mm is a good low light performer & a great all-round lens for travel photography. The Samyang 24mm f 1.4 lens is suitable for both full-frame & cropped sensor cameras. UMC stands for Ultra Multi Coated, which indicates that the lens has been covered with multi-layered, anti-reflective coating which minimises reflections & increases image contrast. This lens is a manual focus lens & does not have autofocus (AF).