Binoculars Carl Zeiss Jena Feldstecher 8 Fach (1)

Magnification: 8x
Aperture (objective diameter): 20 mm
Field of view: 5.1°
Visible field of view (eyepiece FOV): 41°
The closest focusing distance: 7 m
Width: 14.2 cm
Height: 10.7 cm
Weight: 490 g
Production date: 1905.

   60,000 of such devices were released from 1894 to 1908. This is the most massive civic binocular among first three Carl Zeiss Jena prismatic models having 4-x, 6-x and 8-x magnification. Flat prism covers made of brass (the earlier models were made of aluminum) and a central hinge, which is attached to binoculars halves with the help of screws, belong to distinctive features of this 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 and 6-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 20 mm (the earlier model had an aperture equal to 18 mm) and 8x magnification. The binocular’s field of view and the eyepiece’s FOV are enlarged in comparison with the previous model
   This device possesses eyepieces of the so-called "1/3" design (see Hans T.Seeger. Zeiss-Feldstecher, Handfernglaser von 1894-1919, Modelle-Merkmale-Mythos, pp.114-116) with the base diameter equal to 20.5 mm and the top prism cover width equal to 44 mm. The binoculars with such eyepieces design were in mass production approximately from 1903 to 1906 (according to other sources – up to 1905) (see photo). 
   The binoculars frame hinge is attached to its halves with the help of 5 screws from each side. The device has short “lugs” for a jugular strap, which are attached to binoculars with the help of 2 screws (the previous model had longer “lugs”). There are inscriptions “Carl Zeiss, Jena. D.R.P.” on the left prism cover. D.R.P. is an abbreviation for Deutsches Reichs Patent. 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 against the background of Carl Zeiss Tessar photo lens schematic image (the earlier models had an inscription in italics up to 1904) . 
      The binocular’s serial number is "37502" and it was produced in 1905-1906. 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. 
   The earlier model of this binocular with "2/3"-type of eyepieces, inscriptions in italics and specific coffer is available by the following link:
   The earlier model of this binocular with "3/3"-type of eyepieces, inscriptions in italics and unique coffer is available by the following link: