Contax II viewfinder patent

Two versions of a very clever automatic frame changer for rangefinder lenses 50mm, 85mm, 135mm and 180mm.
Why not were used in Kiev RF models?
Regards
LP

Very interesting!

But I wonder if the size of the Contax II/Kiev window is compatible with the first solution: the rotating masks require more space than possible, as it seems. And even the second solution was not used by Zeiss. Perhaps they would have forced to too many modifications?

Anyway, two clever propositions much neater than a turret. Thanks, Luiz!

Amitiйs. Jacques.

Dear Jacques:
Absolutely compatible and and totally feasable.
This clever adaptation should simply be introduced under the front camera chrome escucheon.
See comparative picture
Regards.

Dear Luiz,

When I look at my Contaxes, I cannot imagine that such masks can rotate correctly in such a space... And in your last drawings, it seems that the main window is smaller than the regular ones. I wonder if such propositions would not have lead to modifications in the finder (magnification, etc.)
All that to discuss: we won't have the final word!
Thanks to have awakened me
Amitiйs. Jacques.

when you dismantle the body you will see that the inner exit prism window is much smaller then the outside camera frame.
I image how beautiful would be the rotating wheel made in a transparent green disc emoldurating the original camera field.
observe that this idea came in 1936 just after the first Contax II launch at least 19 years before the automatic frame finder limits of Leica M3 which was too much complicated.
Regards
LP