Bernhard Woldemar Schmidt was an Estonian optician. In 1930 he invented the Schmidt telescope, which corrected for the optical errors of spherical aberration, coma, and astigmatism, making possible for the first time the construction of very large, wide-angled reflective cameras of short exposure time for astronomical research.
Bernhard Schmidt
Schmidt Museum at Hamburg Observatory, Bergedorf
The 2m Schmidt Camera (the Alfred-Jensch Telescope at Karl Schwarzschild Observatory in Tautenburg, Germany).
Naissaar is an island in Estonia. It is located in the Gulf of Finland, northwest of the capital city Tallinn, and is administratively part of Viimsi Parish. The island has an area of 18.6 square kilometres. It is 8 kilometres long and 3.5 kilometres wide, and lies about 8.5 kilometres from the mainland. The highest point on the island is Kunilamägi, which is 27 metres above sea level. The island consists predominantly of coniferous forest and piles of stones and boulders. In 2020, the island had a population of 17; in 2011 the island had about 35 permanent residents and some summer residents.
Naissaar from the air
Kunilamägi
Russian battleship Petropavlovsk
Sailors of the Petropavlovsk in Helsinki, 1917