Kern-Paillard Switar 10mm, H16 RX, W/Focus Lever

The Kern-Paillard Switar 10mm f/1.6 H16 RX is a fast, wide-angle 16mm cine prime designed specifically for Bolex H16 Reflex cameras and comes with preview/focus lever.

At 10mm, it gives a genuinely wide field of view on 16mm film, making it useful for interiors, establishing shots, landscapes and handheld filmmaking where you want plenty in the frame. The f/1.6 maximum aperture also makes it relatively fast for such a compact vintage cine lens.

But the important part of the name is RX.

Bolex H16 Reflex cameras use a prism in the optical path to divert part of the incoming light to the viewfinder. That prism affects optical performance, particularly with shorter focal lengths and wider apertures. Kern-Paillard's RX lenses were specifically corrected to account for that prism.

So while the lens uses a standard C-Mount thread, it's much more specifically a purpose-built lens for the Bolex H16 Reflex system than simply a generic C-Mount 10mm.

It's a proper piece of Swiss-made Bolex cine glass, compact, fast and very much designed for shooting motion picture film.

Best for

• Bolex H16 Reflex cameras
• 16mm filmmaking
• Wide establishing shots
• Interiors
• Landscapes
• Handheld 16mm work
• Low-light filmmaking
• Vintage cine lens collectors
• Experimental filmmaking
• Adaptation to compatible digital cinema systems

What to expect

On standard 16mm, 10mm is a wide-angle focal length, giving considerably more space around your subject than the more normal 25mm lenses commonly associated with Bolex H16 kits.

The f/1.6 maximum aperture makes it useful when available light is limited, while manual focus and aperture give you the direct mechanical control expected from a vintage cine prime.

The C-Mount uses a 1-inch diameter, 32-thread-per-inch mounting thread with a standard 17.52mm flange focal distance.

The RX designation matters most when using it as intended on an H16 Reflex. Bolex's own documentation states that H16 RX lenses are specially corrected to compensate for the camera's reflex prism, particularly when using shorter focal lengths and wider apertures.

It can also be adapted to some modern mirrorless and digital cinema cameras, although compatibility, sensor coverage and resulting image characteristics depend on the camera and adapter being used.

The focus does lock slightly and can be easily fixed with an approved solvent and re-lubrication.