Thingiverse
Pentacon 2.8/80 Projection lens to Nikon F-mount adapter by Kajashey
by Thingiverse
Last crawled date: 4 years, 1 month ago
This is an big tube adapter to fit on the front of a nikon camera and to screw a Pentacon 80mm ƒ/2.8 projection lens into. Get beautiful soap bubble bokeh for so much less than a trioplan lens.
This is not a generic pentacon mount to f-mount. This is one specific slide projector lens (pentacon 2.8/80 AV) to Nikon f-mount. There may even be different sizes of this one lens. This one had a barrel diameter a little over 51mm (over 2 inches). Might be called a Pentagon XL.
This adapter comes in two parts that should snap together but you can glue together if you choose to. Has an internal tooth that fits into a groove on the projector completing a focusing helicoid. The lens can then be twisted to focus. The adapter also has a lip you could glue some scrap felt into to give some dampening.
If you need infinity focus you might have to cut off the last 5mm of the lens's plastic housing so the lens can move in closer to the camera. Be sure to protect the back element of the lens from being scratched while your are cutting. A scratched back element really wrecks the image.
Edit: Added a new Nikon F-mount stub as the last one had some faces missing. Printed fine but was not manifold. The new F-mount adapter is thicker and has much tighter tolerances. Any excess material must be removed for it to fit in the camera.
This is not a generic pentacon mount to f-mount. This is one specific slide projector lens (pentacon 2.8/80 AV) to Nikon f-mount. There may even be different sizes of this one lens. This one had a barrel diameter a little over 51mm (over 2 inches). Might be called a Pentagon XL.
This adapter comes in two parts that should snap together but you can glue together if you choose to. Has an internal tooth that fits into a groove on the projector completing a focusing helicoid. The lens can then be twisted to focus. The adapter also has a lip you could glue some scrap felt into to give some dampening.
If you need infinity focus you might have to cut off the last 5mm of the lens's plastic housing so the lens can move in closer to the camera. Be sure to protect the back element of the lens from being scratched while your are cutting. A scratched back element really wrecks the image.
Edit: Added a new Nikon F-mount stub as the last one had some faces missing. Printed fine but was not manifold. The new F-mount adapter is thicker and has much tighter tolerances. Any excess material must be removed for it to fit in the camera.