Bernhard Schmidt - Last Years

Last Years

Schmidt built his first "Schmidtspiegel"(which came to be known as the Schmidt camera) in 1930, a breakthrough which caused a sensation around the world. He employed a very clever method (the so-called "vacuum pan" method) to make the difficult "corrector plate," so that the system gave superb images. The vacuum pan involved carefully warping a parallel glass plate under partial vacuum into a slight sagging curve and then polishing the upper curve flat. After release of the vacuum, the lens would spring back into the "Schmidt shape" needed for the camera. No one had ever made a lens in this way before.

Schmidt published a brief account (in German) of his invention in professional publications, and offered to build his cameras for professional observatories. Unfortunately, his publicity was too little and his design was too novel. Moreover, the invention coincided with the beginning of the Great Depression. No orders came in and he remained dependent on Schorr and Bergedorf for a modest income from occasional jobs till the end of his life. He produced a larger camera in 1934 and reground the 60cm Bergedorf-Steinheil photographic refractor as well.

Schmidt fell ill at the end of November 1935 after a business trip to Leiden in the Netherlands. Despite attempts at treatment, he died on December 1, 1935 at the age of 56. An autopsy revealed that he was suffering from a lung infection.