Patent GB-760586-A (GB)
Title: Improvements in stereo-photographic methods and apparatus
Inventor: STELLPFLUG AUGUST WILLIAM
IPC: G03B35/10
Filed: 1953-10-02
Abstract: 760,586. Stereoscopic strip film removable magazine cameras. LIONEL CORPORATION. Oct. 2, 1953, No. 27081/53. Classes 98(1) and 98(2) A magazine for use in making stereo pairs on a strip of light sensitive film comprises a frame having a base having two coplanar flanges extending upwardly from its front edge opposite exposure apertures in the magazine spaced from each other and the ends of the base, a first film guiding roller near one end of the base and a second roller at the opposite end, third and fourth rollers between the front coplanar flanges, and a fifth roller behind one of the exposure apertures and between one of the said third and fourth rollers and one of the end rollers, third fourth and fifth rollers being disposed to form a loop in the film so that film areas to be exposed simultaneously are spaced farther apart along the film strip than their spacing at the time of exposure. As shown, a frame member 20 comprises a base 21 from which are bent up front flanges 22-26 and a rear flange 27 and which supports roller 32a-e around which a film 12 is disposed as indicated in Fig. 4, an adhesively joined paper or integral leader strip 11 passing behind the rear flange and being connected to the lightsensitive film which passes round roller 32e, over the backing plate flange 23 at one exposure gate, and behind roller 32d to form an S-loop round rollers 32b, 32c, from which it passes over the second backing plate flange 22 at the other exposure gate, and then round roller 32a to lie against the front of the rear flange 27, the roller 32e being rearmost and the roller 32c being formost on the base with the rollers 32b, 32d in line about a film thickness to the rear of roller 32c and roller 32a a little to the rear of them. The frame 8 is closed at the top, front, and bottom by a U-section cover 35 having apertures 36a, 36b registering with flanges 22, 23 and an inverted U-section shutter 40 having apertures 41a, 41b in its front limb is slidably mounted over the frame and cover. The frame is located between two interfitting box halves 50, 51 which provide between them a light-trapped film exit slot 53a, 53b and are secured together by adhesive tape 58 lying in circumscribing rabbets 57a, 57b. A pin 42 on the shutter projects through a slot 50c in the front box half 50, the apertures 36, 41 being out of register with the pin at the left hand end of the slot. When the closed magazine is slid into the back 60 of a stereoscopic twin lens camera, the pin 42 moves along a slot 63 in the back parallel to the lens axes and enters a gap 65 in a slide 66 movable parallel to the focal plane and the hinged rear door 85 is then closed. Thus on moving the slide 66 to the left the magazine shutter is opened. Simultaneously a pin 72 on the slide moves a slidably mounted plate out of the field of the viewfinder 71. The film is fed by pulling on the leader 11, and at each frame feed the film is arrested by a spring-pressed plunger 80 engaging in one of the holes a<SP>1</SP>-h<SP>1</SP> in the leader so positioning successively for exposure the areas a, A, ..... h, H. The leader is released from the plunger by pressing a button 95 as shown on the camera door 85 when a pin 97 on the button depresses the plunger allowing the leader to be pulled forwardly sufficiently to prevent the plunger re-entering a hole in the leader so that on releasing the button the next frame may be fed. When all eight stereo pairs have been recorded, a spring-mounted pin 56 on the rear box half 50 passes through a stop hole 13 in the film into a hole in the rear flange 27 to prevent the film being drawn out of the magazine. Since on removing the magazine from the camera the magazine shutter is automatically closed, magazines can be changed at any time without waste of film. Due to the spacing of the holes in the leader, the exposed film is in the form shown in Fig. 5. The developed film is cut into four lengths along the unexposed separating portions m ......... q and the related right and left eye pair groups a-d, A-D and e-h, E-H are assembled in two holders for a receiving apparatus.