Canon FD-X 18mm T1.6, which is a great match to the K35s, and unlike the 18mm K35, the FD-X covers full frame sensors. This 18mm especially was designed as a unicorn lens using a Canon FD 24mm f/1.4 L and Angenieux .75x Wide Angle Front Element.  Perfect lens to give you that extra wide lens for a K-35 set so if you want the K35 look, and the field of view of 18mm on a large format sensor, the 18mm T1.6 FD-X is the only option.

• -New circular iris design

• -Less than 10" minimum object distance.

• -143mm common front ring diameter.

• -PL mount; back focus adjustable with standard shims.

• -Covers full frame sensors.

• Common focus and iris gear positions relative to mount flange, same as K35's and FD's.