Binoculars Carl Zeiss Jena Turactem 8x (1)

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: 15 m
Width: 14.5 cm
Height: 10 cm
Weight: 505 g
Production date: 1915.

   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. The early version of Turactem, considered by us, has the ocular bridge shoulders of the same thickness and rather high eyecups (see photo).
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   Turactem is a “civilian” model, this fact is proved by the central focusing mechanism and 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.
   The considered device’s base diameter of the eyepieces is equal to 19.8 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 made of brass and are attached to binocular’s body with the help of three screws.
   There are inscriptions “Carl Zeiss Jenna” on the left prism cover. There is also an inscription “Turactem 458225 8x” 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 binocular’s coffer has features peculiar to the post-war period: a “paramilitary” design with fastenings on the waist belt, the top cover fastening to the coffer’s carcass and specific rivets (see photo). The strap/fastener is not typical for Zeiss coffers and it was probably produced later.
   The binocular’s serial number is “458225” and it was released as a 400 pieces batch in 1915.
   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