This camera is known to have been the first with a pentaprism. After world war II, East Germany was robbed of its intellectual property, and Zeiss Ikon factory was no exception. The Italians, and Russians took what they could from the factory, and this camera's design was produced as Rectaflex in Italy. The mirror in contax S was pulled down by a string during the shutter charging operation. The mirror, and the shutter release wasn't sequential. The mirror, and the shutter were released one at a time as the release button was pressed in. This is how early SLRs were built. In sequential design, if one would hold the mirror's edge after releasing the camera, the shutter won't fire until the mirror reaches its up position, and if one would hold the 2nd shutter curtain by a finger (in the B setting), the mirror won't release until letting go of the 2nd curtain. This is considered sequential.
In Contax S, the mirror is pulled down by a cloth string.
