This is a classic French cine optic: the SOM Berthiot CINOR B 25mm f/1.9 lens, manufactured in Paris. SOM Berthiot was a significant optical firm, and their Cinor lenses are valued by collectors and filmmakers for their compact size and sharp, contrasty image rendering on 16mm film.

The 25mm focal length is the standard or normal perspective for 16mm cine cameras, and its fast f/1.9 maximum aperture ensures excellent light gathering capability, making it a capable workhorse for low-light filming.

The lens features the standard C-Mount screw thread, ensuring compatibility with classic 16mm cameras like Bolex and Beaulieu, and making it easily adaptable to many modern mirrorless digital cameras for creative cinematic use.

Technical Specifications (SOM Berthiot Cinor B 25mm f/1.9)

• Focal Length: 25mm (1 inch)
• Maximum Aperture: f/1.9
• Lens Mount: C-Mount (16mm Cine)
• Aperture Range: f/1.9 to f/1.6 (Manual Control)
• Focusing: Manual Focus (Scale marked in meters: 05m to infinity)
• Origin: Made in Paris, France
• Year of Production: Circa 1950s

Condition Report

The lens is in Good (G) working condition, but shows cosmetic wear commensurate with its age.

• Optics: The glass elements are clear and bright. We detect no fungus or haze. Minor internal dust is expected but does not affect image quality.
• Mechanism: The focusing and aperture rings operate smoothly and correctly.
• Cosmetic: The chrome barrel shows moderate scratching, scuffing, and tarnishing over its surface (visible in images), typical of a used vintage lens. Engravings are clear.