Quote:The main distinction between a Newtonian and a Dobsonian is not the optics, it's the mounting.
Quote:Thanks to everyone for their replies errmmm.Can I focus on its optics ………… ( sorry couldn’t resist that )How exactly DO they differ, focal length, Prim. Sec. mirrors etc. ?Which is better ?
Quote:Quote:The main distinction between a Newtonian and a Dobsonian is not the optics, it's the mounting.On the contrary, being a Newtonian has absolutely nothing to do with the way it's mounted. Newtonian describes an optical system using a concave primary mirror and a flat, diagonally mounted secondary mirror.A Newtonian can be mounted on an equatorial mount or an alt-azimuth mount. A Dobsonian is a Newt on an alt-azimuth mount. Dobsonian Definition
Quote:- we should be clear, a Dobsonian is a type of mount. It is most commonly used to mount a Newtonian telescope but one can use it With refractors and cats.
David W. Knisely . . . . . . "If you aren't having fun in this hobby, you aren't doing it right." Hyde Memorial Observatory http://www.hydeobservatory.info Prairie Astronomy Club http://www.prairieastronomyclub.org
Crazy ATM 6" F9.4 Newtonian first light July 2011 8" F/5.6 Dob, first light June 2003 12.5" F/5 Dob, first light Aug 2007, as well as 9- 4" f/6 mirrors. In progress:12" f/7 on quartz, 18" F/5 on BVC, and a set of 3-8" optical flats All optics by yours truly.
Quote:Thanks to everyone Having read all your replies I will be building a Dobson mount, / Newtonian.Sorry if I have stirred things up a bit !!Shakespeare springs to my mind “ A rose by any other name…… “
Quote:Thanks to everyone Shakespeare springs to my mind “ A rose by any other name…… “
Quote:Quote:Thanks to everyone Shakespeare springs to my mind “ A rose by any other name…… “ Off topic but it brings back memories of high school and I wanted to come up with a literary play on words. Best I could muster was:"A doze by any other name would spell as sleep."Well back to the optics grind.BTW, Newtonian optical configuration - parabolic concave mirror with small diagonally oriented flat mirror to divert the focus to the side of the optical path.--Mike Spooner"Grinder, polisher and sometimes lucky figuring addict."
Edmund 3" f11 reflector (1956), 10" Coulter Odyssey Dob., Astroscan, C90, SV70 ED Refractor,Two C5s, C8, 105mm f15 Yaegers home build refractor with Alt/Azm or EQ mounting options. 8mm Ethos, 35mm & 20mm Clave', 50 mm 2" UO, 40mm Series 5000 SWA, 21mm Baader Hyperion, filled in with RKE's and Celestrons. HyperTuned LXD 75 mount HyperTuned Atlas EQ mount, Canon 18x50 IS Binoculars, Canon 20D.