Originally Posted by yefeihe
I just noticed that both cameras use a Prontor SVS shutter. I wonder if this was actually Prontor's attempt to compete against Compur's interchangeable lens mount used on Retina, Bessamatic etc. The lenses all seem to be marked with "SLK".
Nor sure if anybody is still interested after all these years, but anyway...
It was. The Prontor SLK bayonet was made available to various camera manufacturers to provide interchangeable lens mounts.
Most important ones were Braun, King and Bolta, using the SLK mount for a variety of their camera models. But even though it was very, very similar between Braun Paxette, King Regula and Bolta Photvit 36 cameras, the lenses are not
interchangeable. The SLR mount has been deliberately made incompatible by placing pins for rangefinder actuation and levers for aperture actuation in different locations for Braun, King and Bolta.
So you cannot use a lens intended for a Braun Paxette on a King Regula or vice versa. Between models of the same manufacturer, the lenses should be interchangeable, however. It definitely works for various models of King Regula, I can use any Regula lens on any King SLK bayonet body (IIIc, IIId/IIId Automatic and Super / Super Automatic).