Bartjan

60 CM  MIRROR This one has always been a dream for me. But the prices of the glass!!  When I started thinking about a 60 cm, the price of a disk was ca 5000 dollar.. Suddenly, I heard about  pyrex…

  47 cm f3.9 mirror   The suprax disk measuring 480×40 mm was purchased in 1998 and converted to a f5.1 mirror in 2004. After some years I decided to convert it to a mirror with shorter focal length, just…

  47 cm f5 mirror Jan. 1999 I bought the 48 x4,0 cm Suprax low expansion disk from Beacon Hill telescopes in Cleethorpes (UK) . net price : 408 pounds Spring 1999 I had a f5.1 radius generated in the…

45 cm f thin mirror Introduction: A mirror of 45 cm diameter and only 2,5 cm thickness is something I would really like to posses. True, there is the danger of astigmatism, but think of the ease of handling such…

  40 cm f4.9  Duran(borosilicate) mirror This one proved to be easier than the porthole! Date Work Dec. 2006 406×36 mm borosilicate disc bought from Jilles Eindhoven in Haaksbergen.He had already made a radius of 500 cm in it.Total cost:…

THE 40 CM PORTHOLE MIRROR   In march 2003 I obtained a 405 x24.5 mm float glass disk from St.Helens Specialized Glass .This firm is based near Liverpool. Cost about 80 pounds,of which half was for the shipping to Holland.…

Comes later

Comes later

  25 cm f5.5 thin mirror   The borosilicate disc of 25 cm diameter and 2,5 cm thickness was bought from Stathis Kafalis in Munchen and       a curve belonging to a radius of about 140 cm was…