On 10/4/11, Steve Fisher <iotacass1@hotmail.com> wrote:
Big lenses are coming from China that are about 50/50 as near as I can tell. About half of the folks who get one are really satisfied with them.
Right on! Having owned 3 of the Chinese 5" lenses, I agree. I'll take an old Jaegers doublet over a modern Chinese doublet every time, even if the modern lenses have better coatings. I even worry about Chinese glass being mildly radioactive. Something to think about with eyepieces especially. Makers come, makers go, but the basics never change. Everything is driven by ecconomics. Funny but the SCT as mass-marketed has always been near the bottom of the barrel for optical quality, ever since it was first sold as the Celestron, yet it's still a leader in terms of numbers sold. Putting the corrector in the proper location (at radius, not focus) would put it back in the running in terms of imagery. That was Bernhard Schmidt's original design, not the compact compromise that was Tom Johnson's contribution to commercial telescope manufacture.