Quote:From a marketing point of view, it would be advantageous for Celestron to let people believe that the better solution to Meade's native f/6.3 had been available from the beginning. It sounds as though the truth was that it became truly viable only with the introduction of Celestron's f/6.3 reducer/corrector, but what a great marketing blitz it must have been! Smothered Meade's native f/6.3 in its infancy, with a seemingly objective argument about the size of the central obstruction. The competition between these companies must have been savage.
Uncle Rod Uncle Rod's Astroblog: http://uncle-rods.blogspot.com/
Quote:...You get a alightly wider field of view, but the brightness will only be that of a 6.5" telescope, and the contrast for things like planets will be reduced somewhat.The apture is reduced because to get the focal plane to go far enough to the back to reach the field stop of the eyepiece, the mirror must be moved very far forward using the focuser. When you do this, the outside of the light cone converging on the focal plane is cut off by the baffles in the telescope. And because the outside of the light cone is cut off, rather than being a 34% obstruction, the seconary acts as a 37% obstruction...
Celestron 8SE Dobstuff 13.1": Swayze refigured Coulter mirror, 6 pt mirror cell (2 pt edge support) and CF focuser board made by me StarBlast 4.5 ST80/PortaMount II Zhumell 20x80/Oberwerk 15x70 on a Seronik-style tripod boom mount Hubble Optics 18 inch F/4 mirror.
ROR Observatory Levenhuk 8" carbon fiber RC, Astro Physics CCDT67 Astro-Tech AT8IN w/Moonlite, Baader Mark III MPCC Levenhuk 80mm triplet, Astro Tech 0.8X reducer/flattener Celestron CGEM DX w/HyperTune STF-8300M SX 7 position 36mm CFW Astrodon 5nm H-alpha Little Piney Observatory
Quote:Quote: This still does not prove or disprove that the focal reducer was intended to be part of the C8 kit from the beginningWell, what disproves that is that the reducer/corrector did not appear till nearly 20 years after the C8 was first introduced...There had been reducers (not reducer/correctors) available before then, most of them at f/5, from Celestron and other sources. Once again, the impetus for the r/c was Meade's release of the LX-6 in the late 80s.
Quote: This still does not prove or disprove that the focal reducer was intended to be part of the C8 kit from the beginning
George RoffeKingwood, TX
“I am the only person to ever ace a 1951 USAF resolution test. My 'to observe' list says 'done'. I do not use charts or atlases when I starhop; men do not use maps. One of my sketches won an SBIG deep sky imaging contest. I am the life of star parties I have never attended. I never say anything looks like a faint fuzzy - not even a faint fuzzy. Pilots aim green laser pointers at me. Don Pensack proofreads my CN forum posts.” - The Most Interesting Astronomer in the Universe
Quote:"Just be aware that when you use a 2" diagonal in a C8 behind the 6.3 focal reducer, it will have the effect of turning your telescope into a much smaller telescope."What if you use a 1.25" diagonal behind the FF/FR?Regards,Jim
Friends call me Duane. Compustar C14, Leo Henzl's Custom C8, 6" Refractor Adv. GT mount, 6" F5 Omni XLT Newt., LXD-75 F4 Imaging SN8, Meade 8" F6 Newtonian, EX Dynamax DX6, RV-6 ETX-90 Astro, Meade 2045 4" SCT, B&L 4000 Vixen/Celestron 80mm F11 JC Penny 60mm AZ/ALT Refractor Binos 25x100