Canon and Sigma. Two big names in the lens world. What unifies them?... The Duclos Cine-Mod.
This Cine-Mod was for a pair of Canon 14mm USM lenses and a pair of Sigma EX DG 8mm Fisheye lenses.
The Canon 14mm sports a 114 degree FOV, just out of reach of being a fisheye lens.
The Sigma 8mm fisheye sports a 180 degree FOV with a black frame making for some wacky shots.
Since both of these lenses are wide angle, they would not benefit from a step-up ring. They also both have electronic apertures so they cannot be de-clicked.
The only modification we performed was the focus gears. Each gear is precision cut from a rod of delrin and then installed on the lens. The gears are sturdy yet nondestructive to the lens.
The focus gears were matched as closely as possible to make for an easier lens swap.