Schmidt camera optical axis of the Schmidt design creates a Schmidt-Newtonian telescope. The addition of a convex secondary mirror to the Schmidt design directing light through a hole in the primary mirror creates a Schmidt-Cassegrain telescope. The last two designs are popular with telescope manufacturers because they are compact and use simple spherical optics. A short list of notable and/or large aperture Schmidt cameras. Schmidt camera A Schmidt camera, also referred to as the Schmidt telescope, is a catadioptric astrophotographic telescope designed to provide wide fields of view with limited aberrations. The design was invented by Bernhard Schmidt in 1930. Some notable
Gregorian Institute of Paris Gregorian Institute of Paris The Gregorian Institute of Paris was a pedagogical and religious establishment founded in Paris in 1923 having in view the musicianship of Gregorian chant. This institute was created following a Parisian congress devoted to Gregorian chant and sacred music, held in December 1922. Duting the Second Vatican Council, this establishment became the "Institut de musique liturgique" in 1964, and finally was integrated with the Institut catholique de Paris in 1968, after their long collaboration. In December 1922, a congress of Gregorian chant and sacred music was organized by l'Art Catholique. This conference was a huge success,