3D-printed Argus C3 to LM-EA7 adapter

I just posted Argus C3 Lens To Leica M Body (Techart Pro LM-EA7) Adapter on Thiniverse. The cool thing is that this adapter allows a Sony E/FE body to autofocus these adorable little lenses using a Techart Pro LM-EA7 .

Sony A7RII, LM-EA7, 3D-printed adapter and 35mm, 50mm, and 100mm C3 lenses

The Argus C3 135-film rangefinder camera, made in Ann Arbor, Michigan from 1939-1966, is a bit of American history. About 2 million of "The Brick" were made, and many survive. The interesting thing is that the clunky camera used screw-thread-mount lenses that are simply adorable: tiny and exquisitely well made. Some lenses were made by Bausch & Lomb, others by Enna Werk in Germany, and a few came from Japan. Unfortunately, that doesn't make them great optics -- but they're OK, and did I mention that they're adorable?

Commercial adapters to modern mirrorless cameras are available, but a bit pricey. There is a little problem with inconsistent flange-to-film distances, so many adapters allow some adjustment.

Ok, so why 3D print this one? Well, first, it's really easy to print. Beyond that, I haven't seen any other C3-lens-to-Leica-M-body adapters. With such an adapter, these adorable little lenses can be used with the Techart Pro LM-EA7 adapter ... which makes them able to focus somewhat closer and autofocus. Well, the LM-EA7 can only autofocus if you're within 4.5mm of focus movement from the correct focus, but that works very nicely using the LM-EA7 to tune manual focus: you use manual focus to shift the autofocus range.

Here are a few sample shots, all OOC JPEGs from my Sony A7RII with resizing as the only postprocessing:

Sandmar Wide Angle 35mm f/4.5 @ f/4.5

Cintar 50mm f/3.5 @ f/3.5

Tele-Sandmar 100mm f/4.5 @ f/4.5

Tele-Sandmar 100mm f/4.5 @ f/4.5

All the sample images were shot wide open, and the images are not sharp to the corners, but they are sharp enough (and the lenses get sharper stopped down). Realistically, these lenses don't compete optically with modern lenses, but their old-timey character is nice in small doses....