Samyang SY50M-C EF Cameras Standard-Prime Lens Fixed Prime for Canon EOS 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 A spherical and A spherical 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