Topcon UV Topcor Lens To Sony A7II-series Body Adapter

Topcon is a highly respected Japanese optical company now known for opthalmic equipment, but for a while they made cameras and lenses. The Topcon RE lenses, which use a slightly modified Exakta mount, are exceptionally good. However, Topcon also had a budget line, the UV Topcors. The UV lenses are better than average performers, but neither as fast nor as sharp as the RE lenses. The UV name refers to a coating intended to block ultraviolet light, but many people misunderstand it as meaning the lenses were designed to photograph UV light. There is also difficulty adapting UV lenses to other mounts because the lenses do not have an aperture ring, but rely on an internal coupler to provide aperture control from a ring on the body. The result of all that is UV Topcor lenses being dramatically undervalued: I bought a bunch for about $6/lens!

There have been commercial adapters, but they're rare and expensive. The most common approach is to build an adapter using the mount taken from a Uni, Unirex, or IC-1 camera, but I don't advocate wrecking antique cameras. Thus, the adapter I created is entirely 3D printed, yet it provides a roughly-calibrated aperture control ring. Note that this adapter is a better fit on the A7II-style all-metal E/FE mounts; it's slightly loose on the original NEX E mount.

The first three photos show the adapter on an A7 with 50mm f/2, 100mm f/4, and 200mm f/4 UV Topcors. The last group of photos are taken with various UV Topcors using this adapter on an A7RII. Resolution is probably better suited to 24MP than 42MP full frame, but the lenses have a very pleasant 1960s-style rendering -- certainly way better than one would expect for a $6 lens. My biggest disappointment is that, like many 1960s lenses, they don't focus very close; the last shot required using a short extension tube.