Bernhard Schmidt

Bernhard Schmidt is one of the most renowned staff members in the history of Hamburg Observatory. The optician, born in Estonia, had been interested in science and technology since his early youth. At the age of 11, he lost his right hand and forearm while using gunpowder. He later experimented with homemade cameras.

Bernhard moved to Thuringia to study optics at the Technical University of Mittweida. He remained in Thuringia after his studies, working as a freelance constructor for 25 years. In 1926, he moved to Bergedorf and started working on numerous telescope systems. His research culminated in the invention of the so-called “Schmidt telescope”, a wide-angle camera for astronomy. Through this invention, Schmidt achieved worldwide fame.

Schmidt was a gifted artisan who preferred working alone. He spent most of his time at the observatory in his workshop, where he personally constructed his own optical designs.

Schmidt died young of pneumonia and was buried at the nearby cemetery of Bergedorf, within sight of the observatory.

 

Fig. 1: Bernhard Schmidt in his precision mechanics lab in the main building of the observatory

Fig. 2: Bernhard Schmidt (1879 - 1935)

 

Schmidt Telescopes

Images taken from telescopes with parabolic main mirrors show distortions even at relatively small distances from the optical axis. On these images, stars are point-like only in the centre of the picture; towards the edges, they are increasingly deformed.

This problem impaired complete photographic mapping of the sky and reduced the ability to discover stars and galaxies. Schmidt solved the problem with a new camera, the Schmidt camera, equipped with a corrector plate to compensate for the spherical aberration outside the optical axis.

The main mirror of the telescope is spherical. Schmidt´s first wide-angle telescope, completed in 1930, was a world sensation. After World War II, over 20 large Schmidt telescopes were installed globally.

 

Fig. 3: The original Schmidt telescope (1930). Mirror diameter 44 cm, aperture 36 cm, focal length 62.5 cm.