Cassettes that have a rewind stop for a film take-up reel inside the cassette have been available on the market for a long time. These rewind stops have an advantage in that the exposed roll of film cannot open by itself when the cassette has been taken out of the camera which would cause the last exposed picture to lose its sharpness. However, they have certain disadvantages in that expensive processing steps are necessary in making film fade-outs and fade-ins, and complicated devices must be provided within the camera so as to move the film in the reverse direction past the image aperture regardless of the rewind stop.
Recently, cassettes have become available which are provided with means for releasing the rewind stop thereby making possible the provision of a simple camera design with which fade-outs and fade-ins can be taken. In such cassettes, the device for the release of the rewind stop is coaxial with the take-up pin and generally consists of a rigid jack arrangement and of a notch that may be rotated with the take-up pin. These cassettes differ from other cassettes not only by the inclusion of the device for the release of the rewind stop but by the fact that they have larger outer dimensions.
Well known cameras that may be loaded with both types of cassettes have a spring that acts yieldingly against the release jacks of the device for releasing the rewind stop. During the operation of the camera with a cassette having a releasable rewind stop, the pin shifts the release jacks out of the path of the notch through the tension of the spring making it possible to rewind the film in the camera at will. However, when a cassette without a releasable rewind stop has been placed in the camera, the pin will press directly on the take-up pin rotating in the cassette which is located in the area where the jacks would be located thereby impeding the winding of the film and also placing an additional strain on the camera drive motor. As a result, the life of the batteries of the camera motor is shortened and the exposed film is taken up without any definition.