ALVANDI–PENTAX 67 Helical Focus Mount

(Last update: Oct 8, 2026)

ALVANDI–PENTAX 67 Helical Focus Mount is a new product for photographers who use of Pentax 67 cameras. Some photographers like to use specific large-format lenses on medium-format cameras. One of the most famous is the highly prized Apo-Lanthar lens. Although these lenses are quite old, they can produce a distinctive effect that appeals to certain photographers. However, other photographers may be interested in trying other lenses.

Since the PENTAX 67 is an SLR camera, the mirror box results in a flange-to-film distance of 85 mm. This limitation prevents the use of short-focal-length lenses. Therefore, lenses with a flange focal distance of more than 115 mm and less than 300 mm will be compatible with this system. Lenses with a flange focal distance greater than 300 mm cannot be used, as the corners of the image will be cropped(vignetting).

Due to the variety of lenses, several helical focus mount models have been designed. Each helical focus mount is engraved with the meter and the depth of field scale. The helical focus mount must be calibrated by the consumer for first use.

For heavier, long-focal-length lenses, an Arca-Swiss foot has been designed for tripod mounting, positioning the setup approximately at the lens and camera's center of gravity. Since the weight of the camera and lens is significant, a dedicated grip has been designed on top of it that is detachable. The grip is very practical for carrying and mounting onto a tripod.

The minimum focusing distance of long-focal-length lenses may not be suitable for photographing nearby subjects. For example, the minimum focusing distance of a 300mm lens using a helicoid focusing mount is around 5 meters. This distance is not suitable for portrait photography. To take photographs at distances of less than 5 meters, an Extension Tube must be used. Accordingly, 4 dedicated ALVANDI-PENTAX 67 Extension Tube models have been designed for these lenses to facilitate photography at distances closer than 5 meters. For example, with a 20mm extension tube on a 300mm lens, a minimum focusing distance of 1.5 to 2 meters is achieved. And it is logical that you will lose the infinite. The designed extension tubes lack diaphragm linkage; therefore, they will not be suitable for standard Pentax 67 lenses. Their internal hole diameter is designed to be as large as possible to prevent cropping at the corners of the image(vignetting).

The Helical Focus Mount(HFM) must be calibrated before first use. Use this pdf for calibration.

ALVANDI–PENTAX 67 Helical Focus Mount will be made according to the customer's order. In general, this product is designed for the following lenses. But according to the customer's lenses that are not available in this list, they will be designed and produced.