Binoculars Carl Zeiss Jena Feldstecher 4 Fach

Magnification: 4x
Aperture (objective diameter): 14 mm
Field of view: 10.3°
Visible field of view (eyepiece FOV): 41°
The closest focusing distance: 1.5 m
Width: 14.1 cm
Height: 8.5 cm
Weight: 398 g
Production date: 1916.

   This is a late version of one of the "oldest" Carl Zeiss Jena binoculars’ models. Its objective diameter is equal to 14 mm (the earlier models had an aperture equal to 11 mm) and its magnification is equal to 4x. This binoculars model was produced from 1894 to 1908. A little bit less than 4,000 of such devices were released during that period. This device possesses eyepieces of the so-called "1/3" design (see Hans T.Seeger. Zeiss-Feldstecher, Handfernglaser von 1894-1919, Modelle-Merkmale-Mythos, p.116) with the base diameter equal to 20.5 mm and the top prism cover width equal to 41 mm. The binoculars with such eyepieces design were produced approximately from the end of 1902. Compared with this model’s previous version, the binocular’s field of view was increased from 9.3° to 10.3°. The eyepieces possess a diopter scale and a transverse knurling. The binoculars of such design were produced from 1902 to 1908.
   The binoculars frame hinge is attached to its halves with the help of 5 screws from each side (the earlier models were fixed with the help of 4 screws). The upper and lower prism covers are made of brass, the device has long “lugs” for a neck strap, which are attached to binoculars with the help of 2 screws (the earlier models had shorter “lugs”, which were attached with the help of one screw). There are inscriptions “Carl Zeiss, Jenna” on the left prism cover. There is also an inscription “Feldstecher 4 Fach” – “Binoculars. Magnification=4” on the right prism cover. The inscription is encrusted with the help of silver (?) alloy and is made in block letters against the background of Carl Zeiss Tessar photo lens schematic image (the earlier models had an inscription in italics up to 1904).
   The continuous serial numbering of Carl Zeiss Jena binoculars was absent at that time (it appeared only at the end of 1907); the new serial numbers were assigned according to the new model release or according to the device design changes. Therefore, relying upon the serial number "3110" and upon the binoculars design (the eyepieces joint, the frame hinge fixing) one can assume that the binocular was produced approximately in 1906.
   The previous version of this model is available by the following link: