the FODUA (known as FODIS with its case) was the first camera-based rangefinder from Leitz
Toronto. Leitz marketed this long base rangefinder in 1923 – before the Leica as announced. Earlier, Leitz made much larger rangefinders for specialized uses where precision distance measurement was critical.
After the original Leica cameras were marketed (fixed lens, viewfinder only) The FODIS could be clipped upright in the accessory shoe and adjusted so the large and small circular images of the desired subject coincided.
A few years later, Barnack decided to eliminate a step (transfer of the reading from the rangefinder wheel to the lens). He has his staff design an even smaller rangefinder that was incorporated in the camera. As the Leica lens was focussed, a cam in the lens rotated a tiny prism to align the two rangefinder images. The photographer then had instant feed back that his subject was in sharp focus.
This neatly solved the distance setting allowing large aperture/large focal length lenses to be used on more expensive cameras. Some manufacturers could accommodate the Leitz rangefinder if it was calibrated for the different lens-subject design concept. A FODIS/FODUA intended for a specific non-Leitz make of camera, had the slight distance adjustment engraved on the wheel between the 1 metre/3 foot mark and the infinity mark.
At our 2026 events you may find a separate rangefinder or other item of interest to complement your collection. Our Spring Fair is scheduled to take place May 24th at the Trident Hall. I will pin details and poster to the top of the web site as we near the fair date.
NB. The title of this post was inspired by the 1972 Johny Nash song, “I Can See Clearly Now“.
