view
This is an adapter which can be threaded onto the front of a lens with a 52mm filter size.
photo in the kitchen to test
another view for a quick test
Here is the caption from a listing for another adapter
Miida Universal Stereo Adapter for 35mm SLR
Offered for your consideration is this remarkable Miida Universal Stereo Adapter Model SA-1 made by Marubeni-Iida, circa 1971. It is almost identical in appearance to a famous brand of Stereo Adapter that is now highly sought-after by many stereographers around the world. The female threaded screw mount is designed to fit any lens with 52mm male threads. Ring adapters may accomodate some other sizes (a 55mm adapter is included). It is designed for use with 35mm film SLR cameras only! Any other use would be strictly for experimental purposes.
According to the instructions, the Miida Universal Stereo Adapter is supposed to work with any lens, provided the focal length is from 55-300mm. However, I never had any luck using it with my standard issue 58mm lens. (Perhaps the acceptance angle of my lens is too wide?) Since I'm primarily interested in stereo photography, I never got a different lens for my SLR just so this SA-1 would work with it. I use my "real" stereo cameras, instead. For all I know, the Miida Universal Stereo Adapter may need to be adjusted (internally) by a professional or someone who has the know-how to do that.
I found this Miida Universal Stereo Adapter at an estate sale many years ago. The original owner's daughter (who sold it to me) knew little of its history but it appears to have some tiny screws replaced (that don't fit exactly right) and one missing. A small brass nut is visible at the bottom of the left lens (see images #1 and #3.). It probably fell from the back of one of these screws but it does not move or rattle. These replacement screws do not affect the operation at all; it's just something I thought I should note Perhaps the original screws were misplaced when someone tried to clean the mirrors? I don't know. Also, t appears to be a small disc cover (the size of a US nickel) missing from the bottom of the unit. These things are detailed in the photo illustrations (#6 and #7). T's a slight "rattle" when it's shaken but this stops when the diaphragm knob is turned. It does not seem to be caused by the mirrors; rather, it seems to be the diaphragm curtain making this ever-so-slight noise. The mirrors appear to be bright and clear with no obvious scratches.
