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Message: <blockquote data-quote="Binastro" data-source="post: 3533251" data-attributes="member: 111403">Re posts 28 and 37.At least some of the 70 inch mirrors were I think made by Kodak. I think a price was mentioned.I had read about the two larger ones gifted for astronomy.Also someone got hold of a faulty large mirror and made his own observatory for it. I think the world's largest amateur scope.Hubble was faulty from the start because of an elementary error that a good amateur would have spotted. If the launch had failed nobody would have known.I have also seen a 14inch f/0.75 lens weighing about 350 lbs.The Leica (Leitz) cross channel lens has been well described, but I forget where. Maybe 3,400mm focal length. The weather probably meant it wasn't that effective.New telescopes up to 30 metre aperture cost up to billions.There are other lenses not made public.Million dollar lenses are fairly common.</blockquote>