Doppelfernrohr 10x80 - 20° Carl Zeiss Jena, Ohne Trockenpatrone Modell, Kriegsmarine, circa 1939

Doppelfernrohr 10x80 - 20° produced by Carl Zeiss Jena, around 1939, intended for anti-aircraft batteries installed on Kriegsmarine warships.

This doppelfernrohr was born from the need to have an optic that would allow the identification of enemy aircraft in the distance with extreme promptness and precision. Thanks to a field of vision of 122 meters at a distance of 1000 meters, as well as the 20 degrees of inclination of the eyepieces (unlike the 80 degrees of the previous version) it was possible to have binoculars that not only allowed high performance in the field of vision, but it brought the operator a more natural observation position, intended to extend viewing times without tiring easily.

The binoculars are equipped with a mechanism for inserting two filters (one orange and one dark grey) thanks to which both daytime vision and vision in poor light conditions are possible.

The production of this perfected model began in 1943, due to the pressing German military needs of being able to have an optic that could fulfill sighting and detection tasks without problems arising from it, due to the structural technical quality encountered up to then, on the first examples, which compromised its full functionality in conditions of war use.

It was essential to use binoculars on board ships that had a perfect seal against infiltration and consequent serious fogging of the optics.

For the reasons mentioned above, the Kriegsmarine decided to entrust the project, under Zeiss license, for the creation of the Doppelfernrohr 10x80 - 20° field of view 7° 122 meters at 1000 meters, to three other companies, in order to better optimize the watertightness: "Voigtländer & Sohn A.-G Braunschweig" (ddx), "Optische Praezisions-Werke of Warsaw" (eug) and the Italian "Ducati" of Bologna were contacted and assigned the code "mlr".

It was thanks to the invention of the pressurization system using two valves for the introduction of compressed air inside, conceived by the Italian Ducati in 1942, that all the problems encountered up until then on the first production ended.

Located next to the right eyepiece is the plate showing all the specifications, while under the eyepieces there is the letter "T", in German "Transparenzbelag", which indicates that the lenses are coated with an anti-reflection treatment, which improved light transmission in lenses by 80%. This system was developed and patented on November 1, 1935 by Aleksander Smakula, a member of the Zeiss staff in Jena since 1934.

The storage conditions are excellent, the view is perfectly sharp and collimated and all the mechanisms work perfectly.

Carl Zeiss takes its name from its founder, Carl Zeiss, who on November 17, 1846 chose the small town of Jena, in Thuringia, as the location for his precision optical equipment factory.

Thanks to the severe quality control that Carl Zeiss imposed on his products, going so far as to personally destroy the microscopes that did not pass the tests, the newly formed Zeiss became the official supplier of the University of Jena and received the gold medal of the industrial exhibition in 1861 of Thuringia as the best research instrument produced in Germany, awarded to the Stand I microscope of 1857.

In 1866 the thousandth microscope was produced and the name Zeiss became known throughout European scientific circles. Thanks to studies on the Porro prism, in 1893 Abbe patented double prism binoculars, which accentuated the perception of depth.

The mass production of Zeiss binoculars began in 1894, already at the beginning of the twentieth century more than 30,000 were made, at the beginning of the First World War the quota had risen to 500,000 and, at the end of the Second World War, as many as 2,260,000 were produced binoculars for the civil and military market.

Thanks to studies conducted on the perception of light in low light situations, it was demonstrated that the average dilation of the pupil in an adult is approximately 7 mm. For this reason, the 7x50 mm model was introduced in 1910 and remained on the market until 1917 with few changes to the materials used. In 1926, following the post-war crisis of the First World War with the Treaty of Versailles which bankrupted many important German companies, Zeiss purchased "C.P. GOERZ" and founded Zeiss Ikon in 1926.

In 1937 Zeiss had commercial contacts and factories in more than 29 countries around the world. From 1933 Zeiss acquired interest from the Nazi regime, which balanced production towards military instruments. It successfully produced binoculars with wide-angle optics for military use, pressure-resistant optical systems for U-boats, periscope binoculars for targeting tanks. Furthermore, Zeiss cameras were mounted on the V2s for remote sensing operations of the English coasts.

On 1 November 1935, Zeiss, in the figure of Alexander Smakula, patented a process for the treatment of optical glass with extraordinary results in terms of light transmission. Remained a military secret until 1939, it was adopted on binoculars to reduce ghost images and internal reflections.

During the Second World War, there were numerous bombings against the Zeiss factories. Jena was bombed several times by the Allies starting in 1944. Stuttgart was razed to the ground, although the Contessa-Nettel factory suffered little damage. The bombing of Dresden, in addition to devastating the city, also caused considerable damage to the Zeiss Ikon headquarters.

On April 13, 1945, American military forces entered Jena, surprising themselves that the bombing had not caused any significant damage. The main planetarium was in ruins, while the factories remained operational.