This one is a mystery. There is a Varo Optical company which makes an X-ray lens, but that company is American. This lens is clearly marked “Made in Japan” and has both aperture and focusing helicoid. It came originally in a cine C-mount, but I was able to remove that and adapt it to Sony E mount, and it covers the full 35mm frame with no significant vignetting wide open, which makes me think that it was originally designed for medium format. In any case, it has excellent contrast and an almost complete absence of chromatic aberration, as well as a rather soft, but not bland, bokeh. Even at f1.6 sharpness is decent, and it becomes tack sharp a few stops down. A very interesting lens!
