Binoculars Carl Zeiss Jena Turactem 8x24

Magnification: 8x
Aperture (objective diameter): 24 mm
Field of view: 6.3°
Exit pupil diameter: 3 mm
Visible field of view (eyepiece FOV): 50°
The closest focusing distance: 2.5 m
Width: 14.5 cm
Height: 10.2 cm
Weight: 455 g
Production date: 1924.

   The binocular model with central focusing, namely Turactem 8x, appeared in Zeiss catalog T180 in 1914. The device replaced rather successful Telactem 8x model: Zeiss decided to make a cheaper binocular, so he simplified the Turactem design. The new device turned out to be much smaller and lighter, and respectively, more convenient to use, its field of view decreased (from 6.6° to 6.3°) and aberrations increased.
   Turactem was produced from 1914 until approximately 1932. However, in 1912, there appeared a very rare and little-known model Turactem 8x, which was not included to any catalog: the device had side focusing, not the central one: https://binocollection.com/catalog/binoculars-carl-zeiss-jena-turactem-8x.html
   All subsequent versions of this binocular model have central focusing mechanism, rounded objective covers and they differ from each other only by small design changes.
   Compared with previous Turactem version https://binocollection.com/catalog/binoculars-carl-zeiss-jena-turactem-8x-1.html, the binocular we are considering has ocular bridge shoulders with thickenings closer to hinge axis and lower eyecups (see photo).
IMG_3677IMG_3678IMG_3679
   The weight became less (it was 505 g and became 455 g) and the minimum focusing distance was also reduced significantly - from 15 m to 2.5 m. In addition, the central hinge fixture (clamp), with the help of which the hinge could have been finally fixed depending on the observer’s interpupillary distance, was removed from the binocular’s design.
   Turactem is a “civilian” model; this fact is proved by the central focusing mechanism. The interpupillary distances scale is indicated on the upper hinge disk.
   The considered device’s base diameter of the eyepieces is equal to 20.5 mm and the upper prism cover width is equal to 46 mm (see photo). The eyepieces’ front lens diameter is 10.5 mm. The right eyepiece have a diopter scale and the longitudinal knurling. The binocular’s body height (including upper prism cover) is equal to 68.5 mm; the height without lens frame is 52 mm. The prismatic covers are attached to binocular’s body with the help of one screw.
   There are inscriptions “Carl Zeiss Jenna” on the left prism cover. There is also an inscription “Turactem 1226797 8x24” on the right prism cover. The inscription is made in block letters against the background of Carl Zeiss Tessar photo lens schematic image.
   The binocular’s coffer has features peculiar to a civilian coffer of that period: the top cover fastening to the coffer’s carcass with the help of a metal loop and specific rivets (see photo).
   The binocular’s serial number is “1226797” and it was released as a 100 pieces batch in 1924.
   The Turactem’s "predecessor", namely the Telactem 8x model can be checked by the following link: https://binocollection.com/catalog/binoculars-carl-zeiss-jena-telactem-8x.html 
   The binocular’s model with separate focusing, Turact 8x, can be checked here: https://binocollection.com/catalog/binoculars-carl-zeiss-jena-turact-8x.html