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 chant pop charts and peaked #7 of the UK charts. In the US, the album was released under the title "Chant – Music for the Soul" and peaked at #4 on the Billboard classical charts. It became conventional wisdom that listening to Gregorian chant increased the production of alpha waves in the brain, reinforcing the popular reputation of Gregorian chant as tranquilizing music. Gregorian chant Gregorian chant is the central tradition of Western plainchant, a form of monophonic, unaccompanied sacred song of the Roman Catholic Church. Gregorian chant developed mainly in western and central Europe during the 9th and 10th centuries,