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[Login] Forum Archives · Entrance · Main Index · Search · New user · Who's Online FAQ · Calendar Equipment Discussions >> Eyepieces Previous   Index   Next   Flat   Luigi Postmaster Reged: 07/03/07 Posts: 5272 Loc: MA Re: Second Annual World Cup: Eyepieces       11/03/09 07:24 AM Edit   Reply   Quote   Quick Reply:   Edz says, >>> But probably most important is this, you are using only half the power needed to see the diffraction limit.<<< So, if the idea is to test EPs of a given focal length and not overall telescope performance, I would think using a scope that produces smaller diffraction limited stars in its focal plane would enable you to better discern the resolution performance of the EP than would using a scope where the aberrations and diffraction limit of the OTA produce a large blob and swamp any affect of the EP, no? The angular size of the Airy patern is inversely proportional to the aperture and proportional to the focal length, so the linear size so is fixed for a given f/#. So, for a given focal length EP, a faster f/# will produce a smaller input to the EP making it easier to discern the EP performance wrt resolution. The doubles don't have to be difficult overall, they just need to be difficult for the EP. -------------------- 17.5" f/5 Dob. IM-715 MCT. 120ED. Lunt 60mm Ha. Zeiss, Leica, Fujinon, Nikon, Pentax, Bushnell bins Post Extras       Entire thread Subject Posted by Posted on Second Annual World Cup: Eyepieces jrbarnett 11/01/09 08:16 PM Re: Second Annual World Cup: Eyepieces CollinofAlabama   11/11/09 12:42 AM Re: Second Annual World Cup: Eyepieces Jim Curry   11/05/09 10:18 AM Re: Second Annual World Cup: Eyepieces jrbarnett   11/05/09 11:45 AM Re: Second Annual World Cup: Eyepieces Junn Chavez   11/03/09 05:05 AM Re: Second Annual World Cup: Eyepieces EdZ   11/03/09 06:55 AM Re: Second Annual World Cup: Eyepieces Luigi   11/03/09 07:24 AM Re: Second Annual World Cup: Eyepieces EdZ   11/03/09 09:19 AM Re: Second Annual World Cup: Eyepieces PJ Anway   11/02/09 10:14 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/02/09 10:43 PM Re: Second Annual World Cup: Eyepieces Jeff Morgan   11/02/09 05:39 AM Re: Second Annual World Cup: Eyepieces jrbarnett   11/02/09 01:26 PM Re: Second Annual World Cup: Eyepieces Alvin Huey   11/03/09 02:21 AM Re: Second Annual World Cup: Eyepieces SteveC   11/03/09 09:28 AM Re: Second Annual World Cup: Eyepieces Alvin Huey   11/04/09 02:29 AM Re: Second Annual World Cup: Eyepieces Luigi   11/04/09 07:49 AM Re: Second Annual World Cup: Eyepieces EdZ   11/04/09 09:01 AM Re: Second Annual World Cup: Eyepieces Rob E   11/04/09 10:01 AM Re: Second Annual World Cup: Eyepieces Luigi   11/04/09 01:02 PM Re: Second Annual World Cup: Eyepieces Lake Sky   11/04/09 01:47 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/04/09 02:13 PM Re: Second Annual World Cup: Eyepieces lightfever   11/04/09 08:00 PM Re: Second Annual World Cup: Eyepieces orveko   11/04/09 08:09 PM Re: Second Annual World Cup: Eyepieces PJ Anway   11/04/09 05:02 PM Re: Second Annual World Cup: Eyepieces Luigi   11/05/09 03:57 PM Re: Second Annual World Cup: Eyepieces EdZ   11/05/09 04:27 PM Re: Second Annual World Cup: Eyepieces SteveC   11/05/09 11:50 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/06/09 10:50 AM Re: Second Annual World Cup: Eyepieces SteveC   11/06/09 11:03 AM Re: Second Annual World Cup: Eyepieces Mike Hosea   11/05/09 05:03 PM Re: Second Annual World Cup: Eyepieces Mike Hosea   11/04/09 02:54 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/04/09 03:30 PM Re: Second Annual World Cup: Eyepieces EdZ   11/04/09 04:11 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/04/09 07:00 PM Re: Second Annual World Cup: Eyepieces EdZ   11/05/09 09:56 AM Re: Second Annual World Cup: Eyepieces Mike Hosea   11/05/09 03:08 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/05/09 12:00 PM Re: Second Annual World Cup: Eyepieces EdZ   11/05/09 02:58 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/05/09 04:54 PM Re: Second Annual World Cup: Eyepieces lionel   11/05/09 10:29 PM Re: Second Annual World Cup: Eyepieces ausastronomer   11/05/09 05:40 PM Re: Second Annual World Cup: Eyepieces CounterWeight   11/05/09 06:39 PM Re: Second Annual World Cup: Eyepieces EdZ   11/06/09 06:02 AM Re: Second Annual World Cup: Eyepieces CounterWeight   11/05/09 07:39 PM Re: Second Annual World Cup: Eyepieces Luigi   11/06/09 08:02 AM Re: Second Annual World Cup: Eyepieces leonard   11/09/09 09:01 AM Re: Second Annual World Cup: Eyepieces Mike Hosea   11/09/09 09:48 AM Re: Second Annual World Cup: Eyepieces leonard   11/09/09 10:25 AM Re: Second Annual World Cup: Eyepieces Mike Hosea   11/09/09 11:36 AM Re: Second Annual World Cup: Eyepieces leonard   11/09/09 01:42 PM Re: Second Annual World Cup: Eyepieces EdZ   11/09/09 10:47 AM Re: Second Annual World Cup: Eyepieces EdZ   11/05/09 05:03 PM Re: Second Annual World Cup: Eyepieces Patricko   11/05/09 01:26 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/05/09 02:08 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/03/09 11:30 AM Re: Second Annual World Cup: Eyepieces PJ Anway   11/03/09 07:50 PM Re: Second Annual World Cup: Eyepieces square_peg   11/03/09 09:42 PM Re: Second Annual World Cup: 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Second Annual World Cup: Eyepieces deSitter   11/03/09 02:51 PM Re: Second Annual World Cup: Eyepieces Svezda   11/07/09 09:50 AM Re: Second Annual World Cup: Eyepieces kaaikop   11/07/09 11:47 AM Re: Second Annual World Cup: Eyepieces Svezda   11/07/09 02:14 PM Re: Second Annual World Cup: Eyepieces kaaikop   11/07/09 05:16 PM Re: Second Annual World Cup: Eyepieces Svezda   11/08/09 02:02 AM Re: Second Annual World Cup: Eyepieces jrbarnett   11/03/09 01:21 PM Re: Second Annual World Cup: Eyepieces EdZ   11/02/09 02:04 PM Re: Second Annual World Cup: Eyepieces Svezda   11/05/09 08:28 AM Re: Second Annual World Cup: Eyepieces HandyAndy   11/02/09 04:41 PM Re: Second Annual World Cup: Eyepieces hfjacinto   11/02/09 04:56 PM Re: Second Annual World Cup: Eyepieces nyc_nurse   11/02/09 06:04 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/02/09 11:00 PM Re: Second Annual World Cup: Eyepieces kaaikop   11/02/09 06:54 AM Re: Second Annual World Cup: Eyepieces EdZ   11/02/09 07:26 AM Re: Second Annual World Cup: Eyepieces bcuddihee   11/02/09 08:35 AM Re: Second Annual World Cup: Eyepieces SteveC   11/01/09 08:37 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/01/09 09:31 PM Re: Second Annual World Cup: Eyepieces SteveC   11/01/09 09:58 PM Re: Second Annual World Cup: Eyepieces Mike Hosea   11/02/09 12:37 AM Re: Second Annual World Cup: Eyepieces SteveC   11/02/09 10:31 AM Re: Second Annual World Cup: Eyepieces jrbarnett   11/02/09 12:50 AM Re: Second Annual World Cup: Eyepieces SteveC   11/02/09 10:48 AM Re: Second Annual World Cup: Eyepieces Tiny   11/02/09 01:17 AM Re: Second Annual World Cup: Eyepieces deSitter   11/02/09 04:27 AM Re: Second Annual World Cup: Eyepieces MikeRatcliff   11/01/09 08:40 PM Re: Second Annual World Cup: Eyepieces jrbarnett   11/01/09 08:51 PM Re: Second Annual World Cup: Eyepieces starcam   11/01/09 09:41 PM Re: Second Annual World Cup: Eyepieces hfjacinto   11/01/09 09:15 PM Re: Second Annual World Cup: Eyepieces 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