Gaumont Stereo Spido Ordinaire grand prix 1900 - shutters working- small dial/knob between the two lens is missing - the apertures work and the focus moves the lens panel in and out. Krauss in Paris 1: 6.3, F. The shutter is the is Decaux with air-operated brake allowing 7 speeds of the 1/5 second to the 1/175 second. The magazine contains 12 plates.Principle of the air brake. The air brake played in the former shutter the role of the small clockwork slow speeds of the traditional mechanical shutters. An air brake is like a bicycle pump in miniature. A piston compresses air in a cylinder.
The air escapes from it, either by a gauged, fixed or adjustable opening, or by the play between the piston and the lining. By cocking the shutter, one compresses a spring which, once released, will push the piston which, in its turn, will compress the air. During release, the mechanism "expose", either by releasing one of the two guillotines, or by spreading one or more pallets. When the piston arrives in end of the way, the air being itself escaped, it starts the motion of closing. According to the systems, the time of closing can be regulated either by the tension of the spring, or by varying the exhaust opening, or by the distance covered necessary to closing.There is thus a very large variety of pneumatic shutters. Very early and very rare viewer in great condition, no expert on these things so Info and questions welcomed, one of the best brands for this stereoscope viewers. All items I sell are vintage or antique and may not be as new or when first made and may show signs of wear, age, use, or soiling, rust, dents, scratches, chips, flakes, or states that are other than when originally made. Unless stated, ages of items are unknown. Please ask for more detail information if you are not unsure. More pictures are available upon request. Cet item est dans la catégorie "Cámaras y fotografía\Fotografía vintage\Cámaras vintage\Otros". Le vendeur est "po-agi" et est localisé dans ce pays: ES. Cet article peut être expédié au pays suivant: Monde entier.