It’s come to my attention recently through correspondence with a reader of this blog that my Yashica lens may have been made for Yashica by a small lens maker, Kyoei Optical Company, Ltd.

I had assumed that most of Yashica’s early lenses were made by Tomioka Optical of Tokyo with only a few exceptions. Zunow made some cine lenses for Yashica in the late 1950s and it looks as though Zunow may have made the odd 5.8cm f/1.7 lens that was used on the Yashica Pentamatic II (August 1960 to January 1961) and the lens on the earliest Yashica Lynx 1000.

Pictured below is the subject of this post – my Yashica Super Yashinon-R f/3.5 13.5cm short telephoto lens with a Pentamatic bayonet mount. The lens is further marked with a “K.C. in red on the front lens ring. It’s a compact but heavy pre-set lens with click stops at f/3.5 to f/22.

Below is a similar-looking lens that I found while surfing on Flickr.

His lens is marked Kyoei Optical Acall f/3.5 135mm and is pictured with an Exakta mount while mine is for the Pentamatic bayonet mount (unique to the Yashica Pentamatic). The Yashica lens weighs 390 grams (13.7 oz.) without the lens caps and the Acall lens weighs 360 grams.

Pictured below is the complete set as I received it some years ago. The metal Yashica branded lens cap is 52mm and is felt-lined and fits the lens perfectly. The hood is unmarked and it simply screws into the filter threads on the front of the lens. I also have an unbranded Pentamatic mount plastic rear lens cap which is the only one in my collection. The Pentamatic family of 35mm SLRs were only sold with standard lenses attached. I’ve never seen just a body for sale in its original Yashica factory packaging.

The lens has 12 aperture blades which appear to be common to the Kyoei Acall lens in this focal length.

What’s interesting is that this lens has a red “K.C.” engraved on the lens ring while the Kyoei Acall lens does not. A big guess on my part, and at this point, it’s only a guess, is that it refers to the hard coating used on the glass surfaces. Typically the letter “C” is used to identify that a lens is coated (Canon uses “S.S.C.” for “Super Spectra Coated” as an example). The “K” in “K.C.” may identify that the coating is from Kyoei.

Here’s another image of the Kyoei Acall lens.

So there you have it. Based solely on observation on my part between the two lenses I’ve made the connection to Kyoei Optical. I haven’t seen written information or anything in a Yashica sales brochure that links the two companies together. If you have additional info about Kyoei Super-Acall lenses made for Yashica please share it with me. Kyoei Optical also appears to have made SLR lenses for Petri and they made a bunch of lenses using their own name for use on L39 (LTM) rangefinder bodies.

Thanks for stopping by! – Chris

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