Binoculars Carl Zeiss Jena Feldstecher 12 Fach

   Along with the “civilian” 4x, 6x and 8x Feldstecher binoculars, 4 new “civil” devices were manufactured at the end of 1896: Jagdglas (optics for hunting) Vergr.= 5, Jagdglas Vergr.= 7 1/2, Feldstecher Vergr.= 10 and Feldstecher Vergr. = 12. All of them had objective diameter equal to 24 mm (this value equaled to 25 mm for the binoculars of first releases), the 25 mm eyepiece tube diameter and the 55 mm top prism cover width. The latter had curved design, the so-called “bent shoulders”, which was borrowed from D.F.95 military binoculars, manufactured in 1895. These 4 models were produced in such appearance until 1907/1908 (with an exception of the eyepieces design changes, the upper hinge disc and transition from italics to block letters). Nearly 12,000 of such binoculars were produced between 1896 and 1908. 
   The brass-made prism covers of the so-called “bent shoulders” type and a central hinge, which is attached to binoculars halves with the help of screws belong to distinctive features of Feldstecher 12 Fach model. The civilian application of this model is also proved by the central hinge fixture’s (clamp’s) small diameter (see photo), which has a hole for a knob (included to binoculars delivery kit), with the help of which the hinge could have been finally fixed depending on the observer’s interpupillary distance. The “earlier” 4-x, 6-x, 8-x and 10-x models have the same fixture design. The interpupillary distances scale is indicated on the upper hinge disk (this scale was absent in earlier models and the disc had a flat shape). This model’s objective diameter is equal to 24 mm (the earlier model had an aperture equal to 25 mm) and 12x magnification.
   This device possesses eyepieces of the so-called "2/3" transitional design (see Hans T.Seeger. Zeiss-Feldstecher, Handfernglaser von 1894-1919, Modelle-Merkmale-Mythos, p.97). The binoculars with such eyepieces design were produced approximately from the end of 1898 to 1907 (see photo).
   The binocular’s frame hinge is attached to its halves with the help of 5 screws from each side. The device has long “lugs” for a jugular strap, which are attached to a binocular with the help of 2 screws. There are inscriptions “Carl Zeiss, Jena” on the left prism cover. There is also an inscription “Feldstecher 12 Fach” – “Binoculars. Magnification=12” on the right prism cover. The inscription is encrusted in block letters with the help of silver alloy against the background of Carl Zeiss Tessar photo lens schematic image.
   The eyepieces design of this device was changed compared with the previous version of this model (the field of view was increased from 2.7° up to 3.3°): the eyepiece’s front lens diameter was increased from 9.5 mm to 11 mm.
   The binocular’s serial number is “11460” and it was released in 1906/1907. The continuous serial numbering of all Carl Zeiss Jena binoculars was absent at that time (it appeared only at the end of 1907); however, there exist facts that indicate that the serial numbering was general (continuous) within these 4 models with curved upper prism covers (the so-called “bent shoulders”) (see Hans T. Seeger. Zeiss-Feldstecher, Handfernglaser von 1894-1919, Modelle-Merkmale-Mythos, p. 141 and Production of Carl Zeiss Binoculars 1894-1908. By Thomas Antoniades).
   The binocular is rare and it is preserved in a very good condition. Its coffer has many features peculiar to that period (see Hans T.Seeger. Zeiss Handfernlaser 1919-1946, Modelle-Merkmale-Mythos, pp. 607-627), for example, the upper cover seamless design (Nahtloser Kocher).
   The old version of this model with a smaller field of view is available by the following link: http://binocollection.com/catalog/binoculars-carl-zeiss-jena-feldstecher-vergr12.html