Designed and built to deliver optimum optical performance when wide open, the Leica 135mm T1.4 Summilux-C Lens is part of the C.W. Sonderoptic line of Summilux-C cinema lenses. The Summilux-C lenses all feature a minimum image circle of 33mm, so they each comfortably cover Super 35 without corner softness or darkening. It features a titanium PL mount, a cam-driven focus mechanism, and focus scales marked in feet. The T1.4 maximum aperture is consistent among the range, so there is no concern about exposure variations when cutting between Summilux-C lenses. However unlike other Summilux-C lenses, the minimum aperture of the lens is T16. Each lens incorporates cine-stryle geared focus and iris control rings, which share the same position, so swapping lenses can be done without having to adjust your follow focus or lens control system.
The lens features an internal focus design, which means a non-rotating front perfect for clip-on matte boxes. The 300° of focus rotation provides for accurate focus pulling, and the focus markings from 6' to infinity are consistent across focal lengths. Rear nets can be mounted to the 135mm with an available (but not included) rear net holder. With a front diameter of 116mm, this is the only lens in the Summilux line up that does not have a 95mm front diameter, although the focus and iris gears are consistent with the rest of the lenses in the series. The 135mm lens weighs in at 7.4 pounds.