Binoculars Carl Zeiss Jena Feldstecher 8 Fach (2)

   In 1907, Carl Zeiss radically changed the framework and the design of his binoculars, replacing "civilian" models Feldstecher 6 Fach by Telex, Feldstecher 8 Fach by Telact, Jagdglas by Silvamar and Feldstecher 12 Fach by Telefort. The new devices’ detailed characteristics were published in the 74-th volume of Carl Zeiss catalog in August 1907. The optical characteristics were significantly improved in new devices (the field of view and the objective diameter were increased, optical aberrations were decreased), and the devices’ design was also changed: the central hinge and the “lugs” for a neck strap were not attached to binocular with the help of screws any more, they became integral with it instead, an eccentric objective alignment system appeared and its frame design was also changed, the prism covers spanned the binoculars’ carcass, and they were lubricated with a special compound at the joint points in order to improve impermeability. Moreover, the prisms inside the binoculars were no longer pressed by prism covers – they were fixed with the help of special flat springs instead. It helped increasing the device’s reliability greatly. Actually, the binoculars have survived in such appearance up to present days (see Hans T.Seeger. Zeiss-Feldstecher, Handfernglaser von 1894-1919, Modelle-Merkmale-Mythos, pp.399-414)

 

   However, the process of changing the binoculars "generations" did not happen in a wink, and during 1907-1908 small batches of the new-design devices, having old markings, as well as the binoculars of an old construction, were still produced (for example, a rare binocular http://binocollection.com/catalog/-binoculars-carl-zeiss-jena-feldstecher-8-fach.html)
   The binocular Feldstecher 8 Fach with a serial number 56237 belongs to such rare binoculars, which does not yet belong to new continuous numbering (it possesses an old system  of serial numbering), but it is already made in a new design of Telact 8x binoculars. This device was produced in 1907.
   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 interpupillary distances scale is indicated on the upper hinge disk. This model’s objective diameter is equal to 24 mm (the earlier models had an aperture equal to 20 and 18 mm) and 8x magnification.
   This device possesses eyepieces with the base diameter equal to 24.5 mm and the top prism cover width equal to 50 mm (see photo). The eyepieces have a diopter scale, transverse knurling and eyecups of specific rare shape.
   There are inscriptions “Carl Zeiss Jena” on the left prism cover. There is also an inscription “Feldstecher 8 Fach” on the right prism cover. The inscription is encrusted in block letters with the help of silver alloy (the earlier models had an inscription in italics up to 1904) and it is made against the background of Carl Zeiss Tessar photo lens schematic image.
   The earlier model of this binocular with "2/3"-type of eyepieces, inscriptions in italics and a specific coffer is available by the following link: http://binocollection.com/catalog/binoculars-carl-zeiss-jena-feldstecher-8-fach-1.html
   The earlier model of this binocular with "3/3"-type of eyepieces, inscriptions in italics and a unique coffer is available by the following link: http://binocollection.com/catalog/binoculars-carl-zeiss-jena-feldstecher-vergr8.html