Sigma 50-100mm Cine Zoom 

The Sigma 50-100mm T2 Cine High-Speed Zoom Lens (Feet) with a PL mount
provides an image circle that covers Super 35mm-sized sensors. It features a
maximum T-stop of 2, and the aperture does not ramp over the zoom range.
It shares common lens gear positions with the other lens in the Sigma High
Speed Zoom lineup, which makes for rapid lens changes. What sets this lens
apart from the standard Sigma High Speed Zooms is fully luminescent
markings. When shooting in dim or dark environments, focus pullers and
camera operators will be able to easily discern lens markings without
resorting to distracting lamps or other disruptive light sources.
The 9-bladed iris provides round out of focus highlights for a natural-looking
bokeh. The lens barrel features 180° of rotation from close focus to infinity,
and the zoom barrel rotates 160°, and the clickless iris ring features 60° of
rotation. All three lens control rings are geared with cine-standard 0.8 Mod
gears and the focus scale is marked in feet.