Samyangs 24mm t15 ed as if umc ii video is a wide angle manual focus cine lens designed for full frame and smaller sensor sizes and is known for its beautiful bokeh it has been carefully engineered for professional film and video work with the focus gear ring allowing the use of follow focus systems the decoupled de clicked aperture ring works quietly and smoothly during shooting the stated t number of 15 refers to the actual light transmission of the lens and is particularly important