Astro-Optik is one of a number of German optical companies that flew under the radar, due to its speciality lenses. It was founded in 1922 as Astro-Gesellschaft Bielicke & Co and based in Neukölln, Berlin (which would become part of West-Berlin). The founders were William (Willy) F. Bielicke, Hugh Ivan Gramatzki and Otto (?). Gramatzki (1882-1957) was a successful amateur astronomer and astrophotographer who published in the journal Astronomische Nachrichten, and headed the local branch of “Berliner Astronomische Vereinigung” for a number of years. Gramatzki invented the Transfokator in 1928. Bielicke (1881-1945) a German-American optical designer was involved in the technical development of the lenses and was responsible for the “Tachar” and “Tachon” lenses.

So it is then not surprising that Astro-Berlin’s product range included lenses suitable for astrophotography and astronomical photometry. After the war the company focused on its film technology (Astro-Kino, Astro-Kino Color) developing lenses that had long and extremely long focal lengths, sometimes called “optical heavy artillery”. The company ceased operations in 1991.
The company produced a multitude of lenses, many under the brand Astro-Berlin. Astro-Berlin is likely most famous for its long lenses for cinematography and photography. These lenses were very simple consisting of one (f/5, f/6.3) or two (f/2.3) achromatic doublets. The f/5 lenses for 35mm came in 300mm, 400mm, 500mm, and 640mm lengths. The 800mm f/5 lens was designed for medium 60×60mm format, and the 1000mm f/6.6 for 60×90mm format.
| mm | 125 | 150 | 150 | 200 | 300 | 300 | 400 | 500 | 500 | 640 | 800 | 1000 | 2000 |
| f/ | 2.3 | 2.3 | 1.8 | 3.5 | 3.5 | 5 | 5 | 4.5 | 5 | 5 | 5 | 6.3 | 10 |
In addition they produced quite fast lenses. In 1933 they introduced the Tachor f/0.95 which was available in various focal lengths. The 75mm version was suitable for an 18×24mm format (half-frame) but it was a large lens at 110mm in length with a frontal diameter of 81mm. The longest lens produced was possibly the 2000mm f/10 Astro Telastan. At times Astro also cooperated with the other Berlin optics manufacturers Piesker and Tewe.

These days, Astro-Berlin lenses are expensive on the secondhand market. For example the Astro Berlin Pan Tachar 100mm f/1.8 can sell for up to C$6000 depending on condition. However it is possible to find a 500mm f/5 lens for between C$900-1200.
Further reading:
- Berliner Objektive von ASTRO, Piesker, TEWE und Dr. Weth, PHOTObutMORE
- ASTRO Gesellschaft (a great source on