Talk:BTA-6

Ritchey-Chrétien or Cassegrain Telescope
The article state that the BTA-6 is of Ritchey-Chrétien type. However, the official website (http://www.sao.ru/Doc-en/Telescopes/bta/descrip.html) states that the primary mirror is of parabolic shapes. If correct, this would make the BTA-6 a Cassegrain telescope. A Ritchey-Chrétien system has hyperbolic primary and secondary mirrors while the older and inferior Cassegrain telescope uses a parabolic primary mirror combined with a hyperbolic secondary. --2001:16B8:118E:E200:232C:8D80:D9DE:CC65 (talk) 02:00, 20 December 2020 (UTC)