http://tech.groups.yahoo.com/group/atm_free/ Amateur Telescope Making Thu, 05 Nov 2009 23:15:09 GMT Mark Whitaker http://tech.groups.yahoo.com/group/atm_free/message/14769 http://tech.groups.yahoo.com/group/atm_free/message/14769 Eventually, if you start making optics, you'll buy them all. Just buy everything in Willmann-Bell's telescope making section. Mark Thu, 05 Nov 2009 22:51:00 GMT Jarvis Krumbein http://tech.groups.yahoo.com/group/atm_free/message/14768 http://tech.groups.yahoo.com/group/atm_free/message/14768 Mark, if you are at all interested in the beginning of Amateur Telescope Making, I would recommend the original "Amateur Telescope Making", "Amateur Telescope Thu, 05 Nov 2009 22:06:29 GMT Stephen Koehler http://tech.groups.yahoo.com/group/atm_free/message/14767 http://tech.groups.yahoo.com/group/atm_free/message/14767 Mark, I am taking the advice of Mark and just got a copy of How to Build a ... I would add Star Testing Astronomical Telescopes by Harold Suiter. It's more Thu, 05 Nov 2009 21:55:45 GMT exitar01 http://tech.groups.yahoo.com/group/atm_free/message/14766 http://tech.groups.yahoo.com/group/atm_free/message/14766 Hey guys, I am taking the advice of Mark and just got a copy of How to Build a Telescope by jean Texereau. I've also ordered Telescope Optics. Now I would like Thu, 05 Nov 2009 05:59:44 GMT trulyyours05 http://tech.groups.yahoo.com/group/atm_free/message/14765 http://tech.groups.yahoo.com/group/atm_free/message/14765 Good points. Is Texereau still alive. He would be 90. He was a world class professional telescope maker. IMHO, his book "How to Make a Telescope" is required Wed, 04 Nov 2009 00:35:38 GMT Mark Whitaker http://tech.groups.yahoo.com/group/atm_free/message/14764 http://tech.groups.yahoo.com/group/atm_free/message/14764 The warning is basically the same that Texereau puts forth. When you read it, it almost seems to dissuade the amateur from building the cassegrain. It is a Tue, 03 Nov 2009 18:37:49 GMT trulyyours05 http://tech.groups.yahoo.com/group/atm_free/message/14763 http://tech.groups.yahoo.com/group/atm_free/message/14763 Mark, I admire your spirit. You can indeed actually make a Classical cassegrain, SCT or Ritchey-Chretien. Other amateurs have done it. It's a great challenge Tue, 03 Nov 2009 15:58:33 GMT Exitar01@... http://tech.groups.yahoo.com/group/atm_free/message/14762 http://tech.groups.yahoo.com/group/atm_free/message/14762 He does sound like my high school physics teaher as well, Brother Leahey. But like my former teacher his advice is for you to decern and accept or prove Tue, 03 Nov 2009 15:20:51 GMT trulyyours05 http://tech.groups.yahoo.com/group/atm_free/message/14761 http://tech.groups.yahoo.com/group/atm_free/message/14761 More than humor, more than advice, more like a warning. Al Tue, 03 Nov 2009 14:31:43 GMT Ali Khan http://tech.groups.yahoo.com/group/atm_free/message/14760 http://tech.groups.yahoo.com/group/atm_free/message/14760 Mark I enjoy reading your posts. You remind me of my Australian High School Physics Teacher Father John Burns. There is humour at the end of your post too. Ali Tue, 03 Nov 2009 02:19:40 GMT Jerry http://tech.groups.yahoo.com/group/atm_free/message/14759 http://tech.groups.yahoo.com/group/atm_free/message/14759 ... To make a hole more shallow you want to wear down the walls of the hole. The hole gets wider and the slope of the walls lessens. Jerry Mon, 02 Nov 2009 22:47:12 GMT Mark Whitaker http://tech.groups.yahoo.com/group/atm_free/message/14758 http://tech.groups.yahoo.com/group/atm_free/message/14758 It is a matter of design. Classical cassegrains do not need corrector plates while in the case of the SCT design, it is essential. Most commercial SCT's are Mon, 02 Nov 2009 22:40:25 GMT Jerry http://tech.groups.yahoo.com/group/atm_free/message/14757 http://tech.groups.yahoo.com/group/atm_free/message/14757 Hey! There is another youtube video there. http://www.youtube.com/profile?user=curiosis#p/u/0/iqdaM-yWrtQ You would have to know when to use this one. Mon, 02 Nov 2009 22:26:55 GMT Jerry http://tech.groups.yahoo.com/group/atm_free/message/14756 http://tech.groups.yahoo.com/group/atm_free/message/14756 At f:8 (rounded) you shouldn't need to alter the lap to with stars or trimming spedial shapes into the channel pattern. I suggest that you not press stars into Mon, 02 Nov 2009 21:55:42 GMT exitar01 http://tech.groups.yahoo.com/group/atm_free/message/14755 http://tech.groups.yahoo.com/group/atm_free/message/14755 Hey Guys, I was wondering, I am looking at the secondary mirror for my cassegrain that I'm making. For an 8" secondary mirror (hyperbolic) the size should be