The Cooke S4's are an industry powerhouse.

Cooke S4 optics offer superb optical and mechanical performance, control of flare, distortion, veiling glare and spherical aberrations at full aperture. The cam-type focus mechanism allows for smooth focus adjustments. All S4i lenses feature the electronic /i technology which enables film and digital cameras to automatically record key lens and camera data for every film frame. We include the 100mm at no extra cost.