Not quite; Agfa Isoly cameras, hardly a Diana clone, made 4x4 image on 120 film as well. Isoly I and II are more of toy cameras, and at least Isoly I has simple meniscus lens (it's focusing, though -- a pretty classy touch). I'm not sure about Isoly II, but Isoly III has significantly better 3-element lens and more shutter speeds. Isoly Junior has non-focusing meniscus lens.
Originally Posted by mfobrien
By the way, may I add that Agfa was absolutely brilliant camera builder. The greatest thing about them was that they actually used standard film formats, unlike Kodak that suffered from NIH (Not Invented Here) quite badly. As a result, if you try to use many Kodak cameras now, your options are: a) searching for exotic film formats, often coughing up absurdly large sums of money for pretty mediocre film, b) modifying the camera or c) cutting 120 film are trying not to lose a finger in the process. On the other hand, Agfa's answer to 126 film, Rapid, uses standard 35mm film cut from a bulk roll or pulled out from its original cassette. Rapid cassettes are extremely easy to reload, the cameras often provide a square frame format, just like Instamatic, and most of the Rapid cameras are firmly in the toy camera category. All the Instamatic fun with none of the fuss!