I have found that pinning down precise Koniflex models is a real problem. McKeown only copies verbatim what is in Sugiyama. The latter shows three models: a 1952 Koniflex I, which it is implied - but not explicitly stated - has fixed lenses; a "later version" 1955 Koniflex I, which has a number of significant detail changes and is also said to have interchangeable front lens elements to permit change from standard Hexanon 85mm to "Tele-Koniflex" 135mm; and a 1957 Koniflex IIb with similar (if not the same) interchangeable lenses, but which is wearing the 135mm set under the name of "Tele-Hexanon" in the picture shown. Sugiyama says this had auto-stop winding. The two latter cameras look to have strong similarities in detail fittings, which clearly distinguish them from the first (1952) one shown.
Gordon Lewis' (ed.) usually reliable History of the Japanese Camera shows the first Koniflex I launched in 1952, with the Koniflex II arriving in 1954. It specifically states that this latter model was "the first Japanese twin lens reflex with some capacity for interchangeable lenses; the front element could be exchanged to convert the lens to a medium telephoto". Just to confuse, the picture shown in the 1952 entry looks identical to that shown as from 1955 ("later version" Koniflex I) in Sugiyama...
A useful Japanese website (translated) is linked HERE. The translation is a bit iffy, but I think I deduce that the site creator distinguishes two main models.
The Koniflex I have has details which look like the IIb in Sugiyama, but only the "standard" 85mm lens. It also clearly has details from the later model on the site above.
This is all borne out by the recent worrk of Rebollo and Hoary on Camerapedia. If their analysis is correct, then my camera is a II, on the basis of the later flash terminal.
There are some interesting features rare on Japanese TLRs: the 85mm lens size (the Camerapedia site has more on this); the dual-film design, permitting Kodak's 620 film to be used; the later development into a removable lensboard design.
So, the overall story seems to be:
- Around 1954/5 the original fixed-lens Koniflex was replaced by an interchangeable-front-element model.
- For convenience (if not at the manufacturer's decision) we should probably call these models I and II.
- The later details on the 1955 and 1957 Sugiyama cameras probably distinguish the second model, in which case his attribution of the 1955 one as a "later version" model I is dubious.
- I think my camera here is a Koniflex II for the purpose.
I am very ready to be corrected on this by someone more expert. As always, if you know better, PLEASE CONTACT ME.