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jrbarnett
Eyepiece Hooligan
Reged: 02/28/06
Posts: 4336
Loc: Petaluma, CA
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It's that time of year again...
After the new year, in early January, Dan and I and a few others will be running the trials for the Second Annual Eyepiece "resolution(TM)" World Cup.
This year, I'm thinking fewer eyepieces (there were 20 last year; I want just 10 this year), more observers (there were two main and one proctor/tie-breaker observer last year; I'd like 4 main observers this year), and more targets (the Trapezium was the only target last year; I'd like 3 tough double star targets this year). I have a post in the Double Stars forum asking for target sugegstions. Again the target type will be challenging double stars for the aperture, magnification and seeing conditions. The criteria will be whether all stars are seen, and if so, how clearly/constantly.
As for eyepieces, I'm looking for 10 different eyepieces in the 4mm and 5mm focal lengths. The test bed will be a TEC 140, generating magnification in the 196 to 245 range. I'll be using a TEC i-Turret with 5 slots, meaning that there will be two groups of 5 eyepieces each under examination.
The group winners will be the eyepieces from each group with the highest cumulative score. Scoring will be the sum of all scores awarded by each of the four observers for each of the three targets. This year, however, there will be some "fairness" adjustments if for example several eyepieces in Group A have higher cumulative scores than any eyepiece in Group B. In such case, each eyepiece with a score higher than the Group B winner, up to four, will appear in the final round, with the fifth slot going to the Group B winner even if there's a fifth eyepiece in Group A with a higher cumulative score.
I think the above scenario is unlikely, but you never know. Last year several folks were perturbed when the Pentax XW and Pentax SMC Orthoscopic were eliminated by the 7mm TMB Supermono, despite the fact that they shared the same high score as the TMB. (The winner of the group was picked out of a hat. Scientific, I know.  )
Here are some of my thoughts about 4mm and 5mm contenders:
5.1mm Pentax XO
5mm Pentax SMC Orthoscopic
5mm TMB Supermono
5mm University Abbe Orthoscopic
5mm Pentax XW
5mm Radian
5mm Type 6 Nagler
5mm Takahashi LE
4mm TMB Supermonocentric
5mm TMB Planetary
4mm TMB Planeatry
4mm Meade Research Grade Orthoscopic
I'm open to other suggestions as well. Let 'em rip!
Thanks,
Jim
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"I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me."
- Sir Issac Newton
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orveko
super member
Reged: 02/04/09
Posts: 190
Loc: Chicago
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Other suggestions:
Siebert Star Splitter
Zhumell Z-Series
The former is often touted as being "just as good" or "better" than some well respected eypeieces like the UO HDs. It would be interesting to see how it performs head to head. The latter is often suggested with the TMB Planetary as a best bang for your buck planetary eyepiece, but few detailed comparisons with other eyepieces exist.
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Zhumell Z10 Dobsonian: 1250mm x 250mm (/5)
- Sky & Telescope's Pocket Sky Atlas
- Smart Astronomy Sterling Plössl: 40mm
- Antares Elite Plössls: 25mm, 15mm, 10mm
- Siebert Optics Star Splitters: 7.5mm, 6mm, 5mm
Oberwerk 15x70 Binoculars on a Manfrotto 055XB tripod and 128LP head
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FirstSight
Post Laureate
Reged: 12/26/05
Posts: 3871
Loc: Raleigh, NC
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Since there's a fair number of Ethos owners who are using a 2x Powermate or 2x TV Barlow with the 10E to achieve an effecive 5mm focal length, and with the 8E to achieve an effective 4mm focal length, I'd be curious how these combinations stack up against the standalone premium EPs such as in the 5mm category, the 5mmT6 Nagler or the 5mm Pentax XW. Or, in the 4mm category, whatever head-to-head matchups might seem most appropriate.
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Chris M., aka "First Sight"
Orion XT12i Dob with Moonlite CR-2 focuser
WO Megrez 90 refractor on UniStar Light mount
Nikon 10x50 Binoculars
Edited by FirstSight (11/01/09 08:41 PM)
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SteveC
Carpal Tunnel
Reged: 06/15/06
Posts: 1773
Loc: The Garden State
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Hi Jim,
Is the 5.1mm Pentax XO a typo? Mines states 5mm.
Might I suggest that if you are keeping the field to 10, that you substitute a 4mm ZAO II in place of the 4mm Supermono, since the Supermonos are already represented by the 5mm. I'll be glad to loan you my ZAO II.
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SteveC
TEC 140
Intes Micro 715 deluxe
TEC 110 (on order)
SolarMax 40
Losmandy G-11 w/Gemini, DM-6 w/Sky Commander on SV wood tripod, Vixen Skypod
TEC EP Turret, TMB Supermonos, ZAO II, Naglers, 32mm Konig, 24mm Panoptics, 14mm Meade UWA
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MikeRatcliff
Pooh-Bah
Reged: 06/12/04
Posts: 1327
Loc: Redlands, CA
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Jim,
Maybe just stick with 5mm? 4mm to 5mm is a big difference percentage-wise.
Mike
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16" f/4.9 dob, 1.25" Paracorr, 24 TV Widefield, 18 Circle T ortho, 13 Nagler T6, 12.5 UO ortho,
9 Circle T ortho, 2x TV Barlow 1.25"
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jrbarnett
Eyepiece Hooligan
Reged: 02/28/06
Posts: 4336
Loc: Petaluma, CA
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Possibly Mike. But last year the jump from 7mm to 8mm in 880mm focal length 4-inchers turned out to be irrelevant to the results. There were 2 8mm eyepieces and 2 7mm eyepieces in the quarter finals.
We'll do some pre-testing trials to be sure, to validate the focal length choice and targets are rational (just as we did last year before the "big show").
Thanks for the suggestion.
- Jim
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"I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me."
- Sir Issac Newton
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hfjacinto
Almost got me
Reged: 01/12/09
Posts: 2068
Loc: Union,NJ
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I second the Zhummel Planetary. For $59 I would like to see how well they score.
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C9.25 ASGT 9*50 MM Finder,FT Focuser & 2" Diagonal
Meade LXD 75 6 Inch SNT w 9*50 MM Finder
5,6,9,14.5 MM Zhummel Planetary EPs
13,17,21,24,31,36 MM Baader Hyperion
6.7,8.8 MM Meade UWA & 11 MM Nagler T6
Planetary, OIII and Narrowband Filters
Thousand Oaks Dew Control w Kendrick Heaters
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jrbarnett
Eyepiece Hooligan
Reged: 02/28/06
Posts: 4336
Loc: Petaluma, CA
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Steve, the offer of the 4mm ZAO-II is much appreciated. We'll probably take you up on it. Of course, you may have to deliver it in person and participate in the observations. You'd like the vintage Napa cabernet tasting that follows the observing. Maybe a Sivler Oak ladder tasting from the mid to late 80s. 
As for that Pentax XO, I think the specification is actually 5.1mm though it's labeled a "5". The 2.5mm is really a 2.58mm as well I believe.
- Jim
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"I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me."
- Sir Issac Newton
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jrbarnett
Eyepiece Hooligan
Reged: 02/28/06
Posts: 4336
Loc: Petaluma, CA
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Chris, lots of interest in the Zhumells. I think we'll have to add it in the mix. Thanks for the suggestion.
Regards,
Jim
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"I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me."
- Sir Issac Newton
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starcam
sage
Reged: 09/24/07
Posts: 316
Loc: MD
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It would definitely be interesting seeing how the siebert 4.9 star splitter would stack up. Especially since it is touted as a star splitter. Next 5mm UO HD and the 5mm edge on planetary. To see how they stack up against the higher priced optics and still are being manufactured. Thank you for no more hat tricks.
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Celestron 9.25 SCT f/10 fl/2350
Stellarvue SV102ED2 F/7 fl/710
William Optics Megrez 72mm F/6 fl/432mm
Coronado PST
CG-5
UWAN 28mm
Panoptic 22mm
Televue 7T6,13T6,15wf,11
Pentax XW 7,10,20,40 / XO 5 / Zoom 8-24
RKE 8,12,15,21,28
Hyperion 5,8,17/13
TMB 2.5,4,6II,7,9
Brandon 6,8,12,16
UO HD 7mm
Oberwerk bino 15x70
Burgess 8x42 bino
WO binoviewer
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SteveC
Carpal Tunnel
Reged: 06/15/06
Posts: 1773
Loc: The Garden State
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Quote:
Steve, the offer of the 4mm ZAO-II is much appreciated. We'll probably take you up on it. Of course, you may have to deliver it in person and participate in the observations. You'd like the vintage Napa cabernet tasting that follows the observing. Maybe a Sivler Oak ladder tasting from the mid to late 80s.
Thanks for the invite, perhaps I can clear my schedule. I could bring a second TEC turret for easy EP lock and load.
As for the cabernet, bring a wheelbarrow, because I won't be driving and walking will be rather iffy.
Quote:
As for that Pentax XO, I think the specification is actually 5.1mm though it's labeled a "5". The 2.5mm is really a 2.58mm as well I believe.
Ha! I'm returning mine. I hate when I'm lied to. And to think I was going to take it out for 1st light within the next 5 minutes.
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SteveC
TEC 140
Intes Micro 715 deluxe
TEC 110 (on order)
SolarMax 40
Losmandy G-11 w/Gemini, DM-6 w/Sky Commander on SV wood tripod, Vixen Skypod
TEC EP Turret, TMB Supermonos, ZAO II, Naglers, 32mm Konig, 24mm Panoptics, 14mm Meade UWA
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Mike Hosea
Post Laureate
Reged: 09/24/03
Posts: 3924
Loc: "Metrowest" Boston
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Quote:
I hate when I'm lied to.
Steve, you're my favorite eyepiece forum poster of all time! 
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Mike
Stuff that I use:
- 7" f/6.7 home-built Newt, eq platform, Pentax 40XW and 5XO, Tele Vue 13E and 2x Barlow, ZAO-II 6mm
- 120mm f/8.3 home-built grab-n-go Newt with 7-21mm Nikon Zoom
- Canon 15x50 IS and Eagle Optics 12x50 Ranger binoculars
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jrbarnett
Eyepiece Hooligan
Reged: 02/28/06
Posts: 4336
Loc: Petaluma, CA
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Perhaps a class action like the ones in the 80s against monitor manufacturers for advertising "15-inch diagonal" on monitors which were actually only 14.58-inched diagonally?
The audacity! Errors of 0.1mm and 0.08mm, respectively.
But before you return the mis-represented 5.1mm XO, perhaps we could borrow it, too, for testing.
Regards,
Jim
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"I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me."
- Sir Issac Newton
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Tiny
super member
Reged: 05/02/08
Posts: 191
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Just a few more to put out there
Explore Scientific 82* 4.7mm [more competition for said nagler]
Baader Hyperion 5mm
Vixen LVW 5mm [interested how this compares to the Pentax XW, and overall, given the high price point]
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deSitter
Carpal Tunnel
Reged: 12/09/04
Posts: 2926
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Throw in a cheapie or two - GSO Super View or Meade 4000 Plossl 6.4mm. I think it would be better to stay in the 6-8mm range as they are more typical observing choices. You can then test the Pentax XF 8mm, which I predict would finish strong but be bested by some Ortho.
-drl
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Jeff Morgan
Carpal Tunnel
Reged: 09/28/03
Posts: 1985
Loc: Prescott, AZ
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An ambitious project, but it will only tell us how these eyepieces do with refractors. Add a Newtonian and a SCT to the mix.
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Jeff Morgan
Prescott, AZ
Wile E. Coyote School of Telescope Making
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kaaikop
scholastic sledgehammer
Reged: 07/13/08
Posts: 766
Loc: North of the Montreal nebula
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Another vote for the LVW (just curious to see how it fares vs a Nagler...
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Benoit, RASC Montreal
-C9.25 on EQ6 Pro - C6/ED80 on Portamount
-TV Plossls, Radians, Nags, Pans, UO Orthos.
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 14710
Loc: Cumberland, R I , USA42N71.4W
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Doubles for Testing Limits of 80mm to 150mm
you'll be pretty much down near the low end of this list. However, you will find a pair even with a seemingly wider than do-able separation, if it has more uneven magnitudes, will prove quite difficult, so 1.3" with a 2 magnitude difference mayl be a bit more of a challenge than it might first seem.
Probably some of these need to be checked in the 6th Orbit Catalogue, since they have been changing, but perhaps by only a few hundreths arcsec. For example I have zeta Cnclisted at 0.98", but it is at 1.04" in 2009 and will be at 1.06" in 2010.
My opinion is you will probably need to be looking at stars well above the diffraction limit, since you are not using magnifications that will support reaching the limits. Your scope has a limit perhaps as low as 0.9", but it would take probably well over 400x to see that completely separated. To see details in the rings, such as depth of notch or percent overlap, you'd probably need 500x. Furthermore, that low limit will be affected by the magnitudes and the color of the pairs you select. But probably most important is this, you are using only half the power needed to see the diffraction limit. At best, with the powers you are using, you'd simply see that as elongated, perhaps slightly notched. So, I think if you want to see diffraction patterns and details that will help qualify one eyepiece from another, you'll probably be well above the diffraction limit.
Just a heads up, differences in magnification are going to make all the difference in the world on what can be seen and what can't, especially at the resolution limit, and you have quite a wide difference in magnification there. You might find you need to use even slightly wider pairs for the lower power eyepieces in your test group.
Since you might need to use different target separations for each of these eyepiece powers, then it might be wise to include, whenever possible, both the 4mm and 5mm from the same set. For instance, include a 4mm and 5mm University Abbe Orthoscopic, 4mm and 5mm TMB Planetary, 4mm and 5mm Radian, etc.
I noticed you mentioned that Sirius would be one of your doubles targets. A formidable challenge, but just my opinion, Sirius might be more a test of contrast, not resolution.
edz
Edited by EdZ (11/02/09 10:29 AM)
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bcuddihee
Pooh-Bah
Reged: 11/04/06
Posts: 1401
Loc: Cincinnati Ohio
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I know its not a sexy choice but I too would like to see how the lowly GSO's stack up.
bc
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B Cuddihee
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1968 Jason Empire 60X700mm refractor (my buddy from way back)
Celestron Nexstar8SE aka "The Bumblebee",(there is no way this scope should perform as well as it does...but it does)
Feathertouch Microfocuser
Stellarvue 50mm "Sparrowhawk" finder
Denk bino's with Power x switch
Pair of Smart Astronomy 19 EF's (great ep's for binos)
Pair of Edmund 28 plossls
Pair of Edmund 28 RKE'S
Pair of tv 20mm plossls
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SteveC
Carpal Tunnel
Reged: 06/15/06
Posts: 1773
Loc: The Garden State
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Quote:
Quote:
I hate when I'm lied to.
Steve, you're my favorite eyepiece forum poster of all time!
Even the morally and spiritually corrupt have their limits.
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SteveC
TEC 140
Intes Micro 715 deluxe
TEC 110 (on order)
SolarMax 40
Losmandy G-11 w/Gemini, DM-6 w/Sky Commander on SV wood tripod, Vixen Skypod
TEC EP Turret, TMB Supermonos, ZAO II, Naglers, 32mm Konig, 24mm Panoptics, 14mm Meade UWA
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