Originally posted by titrisol There is a RF under the flap, with frame lines for 50-35-90mm. (I wrote a
post here)
The 2nd version of the camera extended the RF base to match the 130mm lens which was new.
The 130mm focuses fine with the RF but needs an extra VF to get the framing right.
The extra VF even has a focusing ring
Ambi Silette - Camera-wiki.org - The free camera encyclopedia A very interesting design and a few clever innovations. Shading the rangefinder/viewfinder windows by the flap when in the up position would seem like an advantage, but such flaps are vulnerable to damage and slow down picture taking just a tad. Perhaps that is why it was eliminated when they introduced an "improved" model with a longer base rangefinder for the 130mm lens.
CORRECTION: The model II still has the rangefinder/viewfinder cover, but it is hard to see in the mage in the link that titrisol posted.
Supposedly, Leitz determined that 135mm was longest FL that their rangefinder could focus accurately, and consequently that somewhat improbable focal length was a must-have for every lens maker during the film SLR era, with many lens-makers offering two and sometimes three 35mm lenses with different apertures. SFAIK, 135mm lenses have been offered with apertures of f4, f3.5, f2.8, f2.3. f2, f1.8 and f1.4, and both Canon & Nikon have offered a 135mm "soft" or "de-focus" lens.