Feinmess was founded by Gustav Heyde (1846-1930) in Dresden (1872) as Gustav Heyde – Mathematical-Mechanical Institute & Optical Precision Workshop (Feinmess roughly translates to “fine measurement”). The company produced astronomical and geodetic precision devices: binoculars, domes and refractors for observatories, telescopes, theodolites (land surveying devices), hand-held rangefinders for aerotopography, and actino-photometers (light meters). From 1931 the company was converted to a limited partnership and concentrated on arms production. In 1945 the company operated under the name Gustav Heyde GmbH. After the war the company was expropriated by the state of Saxony operating as Optik, VVB für feinmechanische und optische Geräte. Finally in 1948 it changed its name to Optik – Feinmess Dresden VEB.

In the 1950s, Welta (Freital) requested a lens for their Belfoca 1 and 2, medium format cameras. There was so much demand for lenses that Feinmess accepted the order, never having produced lenses before. The optical design office was set up by Ihagee, and work on the design of the lens was taken over by Claus Lieberwirth is August 1953. From 1954 the Bonotar was created as a 105mm, f/4.5 lens. A second lens, the 105mm f/6.5 Bonar was derived from the Bonotar. Both lenses were simple in construction, and inexpensive. About 20,000 M42 and 4,000 Exakta mount Bonotars were produced. The lens established itself as a cheaper alternative to the popular Meyer Optik Trioplan. In 1960 production of both lenses was halted, and the optics department was eventually merged into VEB Carl Zeiss Jena.

Interestingly, VEB Feinmess was used in the 1950s as “shield” company, especially for patent applications related to VEB Zeiss Ikon, due to the issues with Zeiss-Ikon Stuttgart. This is why camera patents for well known GDR products are the property of VEB Feinmess, until the founding of VEB Kamera-and-Kinowerk in 1959. There are literally hundreds of patents for lenses, viewfinder systems, motor winding systems, and viewfinder cameras (to name but a few) − all products that Feinmess did not manufacture.

The company still exists today, recently renamed from Feinmess Dresden GmbH to Steinmeyer Mechatronik GmbH, and makes various measuring instruments, positioning systems and optical devices. Bonotar 105mm lenses can be found for between €60-90.

Notable lenses: Bonotar 105mm f/4.5