Binoculars Carl Zeiss Jena Stenotar 5x12

Magnification: 5x
Aperture (objective diameter): 12 mm
Field of view: 8.3°
Visible field of view (eyepiece): 42°
Outlet pupil diameter: 2.4 mm
The closest focusing distance: 1 m
Width: 5 cm
Height (folded): 10.5 cm
Weight: 130 g
Production date: 1924.

   In 1924, the compact Carl Zeiss Stenor 5x binoculars were replaced by the Carl Zeiss Stenotar 5x. It also has a 5x magnification, 12mm lenses, but has a simpler (one bridge) design and lighter weight. The Stenotar also uses Sprenger-Lehmann monolithic "roof" prisms, the use of which gives the binoculars high light transmission.? 
   The lenses of these binoculars are much closer together than the Stenora. This design has had the effect of reducing the plasticity (3D effect) of this instrument.
   Stenotar was produced for a short time: from 1924 to 1930/31. The binoculars were not very popular (apparently, they could not compete with other compact "flat" Carl Zeiss binoculars - Telita and Turita)
   The device has one central hinge, on the upper washer of which a scale of interpupillary distances is applied.
   The eyepiece bodies have a diagonal (at an angle of 45 degrees) knurling, the eyepiece base diameter is 13 mm. The height of the prism bodies is 24 mm, the width is 54 mm, and the thickness is 17 mm. The prism covers are attached to the body with three screws. The focusing of the device is separate. Lens diameter - 15 mm.
   The inscriptions on the left cover of the prism body are "Carl Zeiss". On the right cover - "Stenotar 1229701 5x12". The inscription is printed in block letters against the background of a schematic image of a Carl Zeiss Tessar photographic lens.
   The binoculars come with an original leather case (see photo)
   The serial number of the binoculars is 1229701, it was made in 1924 and was included in the very first batch of 500 pieces.