Rokinon 50mm F1.4 Lens for Canon EF Digital SLR High performance, fast F1.4 aperture, "standard" 50mm prime lens with Full Frame Sensor Coverage Specialized Ultra Multi-Coating (UMC) improves light transmission and reduces ghosting and flare Internal Focusing design (IF) provides non rotating 77mm filter threads and close focusing to 17.7 Inches Hybrid Aspherical and Aspherical lens elements control aberrations for clear and color-accurate images Equipped with an 8 Blade Circular Diaphragm for pleasing Bokeh and a large rubberized focusing ring for quiet and silky smooth control of focus