· Get a Cloudy Nights T-Shirt · Submit a Review / Article    Click here if you are having trouble logging into the forums Cloudy Nights - Official Forums of the 2009 International Year of Astronomy Privacy Policy | Please read our Terms of Service | Signup and Troubleshooting FAQ | Problems? PM a Red or a Green Gu.... uh, User   You are not logged in. [Login] Forum Archives · Entrance · Main Index · Search · New user · Who's Online FAQ · Calendar Equipment Discussions >> Binoculars Previous   Index   Next   Threaded   Pages: 1 gb_astro super member Reged: 01/01/08 Posts: 140 Loc: Sydney, Australia Oberwerk's 100/45 clear aperture?       #3344316 - 09/20/09 04:55 AM Edit   Reply   Quote Quick Reply   Anyone advise the maximum eyepiece field stop I would want to use with Oberwerk's 100/45 deg binos? I am just assuming that there is no point using a field stop larger than the clear aperture of the binos. Would this be correct? Thanks in advance, gb. Post Extras:       charen Pooh-Bah Reged: 05/28/05 Posts: 1082 Loc: New Zealand Re: Oberwerk's 100/45 clear aperture? [Re: gb_astro]       #3346074 - 09/21/09 02:23 AM Edit   Reply   Quote Quick Reply   If you see the above forum thread 'True Aperture' in relation to this reply. I measured the Oberwerk 100-45 degree B.T.s with the standard 25mm EPs at 91 mm clear aperture. Chris -------------------- 35 binos. 80mm Cat. WO66ED SV NH 80mm / EQ3 Meade 8in.LX90 Skywatcher Equinox ED120 / Goto HEQ5. Post Extras:       EdZ Professor EdZ Reged: 02/15/02 Posts: 14719 Loc: Cumberland, R I , USA42N71.4W Re: Oberwerk's 100/45 clear aperture? [Re: charen]       #3346194 - 09/21/09 06:54 AM Edit   Reply   Quote Quick Reply   However, these two uses of the term clear aperture have nothing in common. The 91mm may be the effective aperture. the clear aperture that would be used to determine maximum eyepiece field stop would most likely be the clear opening directly in front of the eyepiece field stop. FWIW, (although this may be different in the 45° version), the clear aperture in the straight thru BT100 is larger than the widest possible 1.25" eyepiece field stop. edz -------------------- Teach a kid something today. The feeling you'll get is one of life's greatest rewards. member#21 Post Extras:       gb_astro super member Reged: 01/01/08 Posts: 140 Loc: Sydney, Australia Re: Oberwerk's 100/45 clear aperture? [Re: EdZ]       #3346200 - 09/21/09 07:06 AM Edit   Reply   Quote Quick Reply   Chris, edz thanks for the replies. Yes I was thinking more of "the clear opening directly in front of the eyepiece field stop" but only because of reading about clear aperture in binoviewers. gb. Edited by gb_astro (09/21/09 07:48 AM) Post Extras:       charen Pooh-Bah Reged: 05/28/05 Posts: 1082 Loc: New Zealand Re: Oberwerk's 100/45 clear aperture? [Re: gb_astro]       #3348238 - 09/22/09 02:38 AM Edit   Reply   Quote Quick Reply   Sorry I replied incorrectly via my misunderstanding. Chris -------------------- 35 binos. 80mm Cat. WO66ED SV NH 80mm / EQ3 Meade 8in.LX90 Skywatcher Equinox ED120 / Goto HEQ5. Post Extras:       Pages: 1 Previous   Index   Next   Threaded   Extra information 9 registered and 18 anonymous users are browsing this forum. Moderator:  EdZ  Print Thread Forum Permissions       You cannot start new topics       You cannot reply to topics       HTML is disabled       UBBCode is enabled Thread views: 258 Jump to *International Year of Astronomy 2009* -----   Global Coordination   Cornerstone Projects   Special Projects   Special Task Groups   Global Activities   National and Regional Activities   IYA 2009 in Africa   IYA 2009 in the USA*Announcements and News* -----   Cloudy Nights Announcements   Discussion of CN Articles, Reviews, and Reports   Beginners Forum   Celestial Events   Light Pollution*Equipment Discussions* -----   ATM, Optics and DIY Forum   Binoculars   Binoviewers   Cats & Casses   Classic Telescopes   Equipment   Eyepieces   Mounts   Observatories   Reflectors   Refractors    Celestron SkyScout and Meade mySky   Video and Electronically Assisted Astronomy*Astrophotography and Sketching* -----   Beginning and Intermediate Imaging   Film Astrophotography   DSLR & Digital Camera Astro Imaging & Processing   CCD Imaging & Processing   Solar System Imaging & Processing   Sketching   Astro Imaging/Sketching Contest *Observing* -----   NEO   General Observing   Planetary and Solar System Observing   Lunar Observing   Deep Sky Observing   Double Star Observing   Solar   Variable Star Observing and Radio Astronomy*Telescope Specific Forums* -----   Celestron NexStar    NexStar GPS / CPC Telescopes   Questar Forum   Meade ACF/RCX / LX / GPS    Meade ETX*Other* -----   Science of Astronomy & Space Exploration   AstroWebsites   Space Rocks*Speciality Forums* -----   AstroArt   Astronomy Software & Computers   Stellar Media   Astro Outreach, Clubs and Star Parties*CN Feedback and Vendor Announcements* -----   Vendor and Group Announcements CN Forums Home

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