The Rodenstock TV-Heligon 75mm f1.1 is an industrial lens, so it’s not going to mount directly to any camera: this is a DIY job. Covers APS-C wide open- might be able to do full frame at closer focal distances- but flange distance is minuscule, so assume close-up only (to a maximum of about 4 feet or so.) Unlike most of these lenses, there is a diaphragm here, though it’s front-mounted and restricts image circle when stopped down; there is no focusing helicoid. An experimental lens in excellent condition: there are a few very light front element marks, but the interior is clean, free of haze or fungus.