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ronharper
scholastic sledgehammer
Reged: 02/14/06
Posts: 876
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Last night I looked at the double star 100 Hercules with my 10x50. It is a good test for this power, at 6.0 and 6.0 magnitude, with a 14.2 arcsec separation, according to a list on Eagle Creek Observatory's website.
I had tried a couple of nights before and failed to split it, but last night it came clean, barely, with a nice dark space. I had just tweaked the focus, which I rarely touch, a tiny bit, maybe that made the difference. In a true 10.0x, this would come out apparently separated by 2.37 arcmin. But the "10x50" I used (Fujinon) was measured by EdZ to have a true magnification of 10.4x, so if mine is like his, I had 2.46 arcmin to work with. I don't think I could have split it with any less than I had.
A curious thing about 100 Her is that it is located just south of a keystone-shaped asterism that looks just like the main body of Hercules proper. Cosmic, huh?
Can anybody split this with a genuine 10x? I bet 10x42 or 10x32 would be better than 10x50--less light to deal with and probably smaller spots. Less than 10x, no way! How about 11x56?
Ron
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Mark9473
Carpal Tunnel
Reged: 07/21/05
Posts: 2519
Loc: 51°N 4°E
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It sounds like this would be a nice challenge object for my 8.5x44 but I'd probably need a very transparent and steady sky to split it - maybe after the summer. It doesn't sound much more difficult than 59 And (6.1-6.7-16.5") which was fairly easy at 8.5x.
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Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50
WO Megrez II 80 FD
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ronharper
scholastic sledgehammer
Reged: 02/14/06
Posts: 876
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Mark,
You and the 804 are a tough combination. Let us know what happens. Hmm, I could try my wife's 8.5x, but I don't think I stand a chance.
Ron
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12102
Loc: Cumberland, R I , USA42N71.4W
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I've resolved it in a 12x50, but can't find any record of ever having seen it better than clearly elongated in a 10x50. it is one of my most observed doubles. I've probably recorded several hundred observations of this one.
I've never been able to see it an any 8x binoc, but with good reason. An 8x observation of a 14.2" double would put the observer among the best in the world, not only in this day and age, but all ages past.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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starramus
Pooh-Bah
Reged: 09/01/04
Posts: 1124
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I dunno. I usually use the brute force method and use my 16X70 Fujinons on it. It is such an easy split with these. I could paint the bathroom with a Q-tip too, but what would be the point? I do not have the Fuji 10X50s, but that may change soon. I didn't dare try the Fuji 7X50s on it so I used my old Celestron 11X80s the closest that i had at hand. I too could only achieve an elongation. I guess good Japanese optics are outdone by better Japanese optics even at lower power.
Regards and clear skies,
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ronharper
scholastic sledgehammer
Reged: 02/14/06
Posts: 876
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What's wrong with me? I like to do more with less. This is my idea of binocular astronomy. But, worse than that, for some strange reason, I like to see the tiniest thing I possibly can. Saying it makes me realize how weird it is, what a paltry substitute for "a life".
Frankly, having observed it often with a 16x70 and finding it close enough for comfort already, I was surprised to split it with such a low power. It was a momentary thing, not "held". When it split, it was like I had crossed the finish line. I quit immediately, and took a big deep breath.
Indeed 100 Her is a lovely piece of cake with my 16x70. But, you know, the stars look smaller with it stopped down to 50mm. Ooops, there I go!
By the way, I received a PM from a member who I will not name, who split it with an 11x56.
Ed, keep slamming. Your eyes are better than mine and you haven't had the Fujinon 10x50 for long.
Starramus, thank you for trying, and for thinking about just what the heck we call ourselves doing here anyway. Your failure doesn't surprise me, however, no offense to you or your equipment. llx is marginal, and a 7mm exit pupil requires extremely fine eyesight to see very sharply with. Stop that baby down and re-torture yourself, please.
Ron
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RichD
super member
Reged: 11/08/07
Posts: 158
Loc: Derbyshire, UK
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Fujinon 10x50 fmt-sx arrived yesterday (finally pulled the trigger after deliberating for months) will let you know how i get on with 100 Her Ron.
By the way, it was your very positive reviews of this binocular that tipped me over the edge Ron! A cursory glance at Vulpecula through cloud last night confirmed your impressions - big,bright and sharp all over.
Oh and it definitely isn't strange to try to find the limit of your equipment.You are not alone!
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Clear skies
Rich
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ronharper
scholastic sledgehammer
Reged: 02/14/06
Posts: 876
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Rich,
Congratulations on the new Fujinon. I still feel the same way about mine. It's view of stars beats anything else I've seen.
Still, with peoples' individual differences, you just never know with binoculars. First impressions are usually correct, but let us know what you think after you give it a good try.
Ron
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Mark9473
Carpal Tunnel
Reged: 07/21/05
Posts: 2519
Loc: 51°N 4°E
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I was going to make splitting 100 Her at 8.5x my project for the summer, but in 10 seconds it was all over.
I went out under a mag 3.5-4 sky - with the waxing gibbous Moon and perpetual twilight here at 51 degrees North, it just doesn't get better. Vega was a bright beacon of course, and all I needed to hop 12 degrees to the southwest, to the little asterism in Hercules dominated by zeta and omicron Her.
100 Her was immediately spotted and seen to be more than a single dot of light. Centered it, adjusted focus a tiny bit, and it was split!
At 8.5x the image scale for watching doubles is minuscule, and sometimes it is difficult to see if the two components are touching or split, but here there was not much doubt. In fact, I noticed that the double cycled between touching an split in sync with my heartbeat.
100 Her has instantly become a favourite target as it is quite a spectacular sight. But the hunt was over so quickly that it's almost a shame it didn't put up more of a fight.
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Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50
WO Megrez II 80 FD
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rookie
super member
Reged: 01/14/06
Posts: 168
Loc: St Petersburg, FL
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Quote:
it is one of my most observed doubles. I've probably recorded several hundred observations of this one.
edz
Ed
I'm amazed anyone can make such a statement. It puts into perspective your background. Do you log your observations with pencil & paper or do you use a software program? 
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Shirley
Celestron CPC 800XLT
Garrett 0ptical BT80~45degree
Celestron Ultima 9x63 & Regal LX 10x42
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12102
Loc: Cumberland, R I , USA42N71.4W
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Rookie, I keep written notebooks. Other doubles that fit the same description are Alya (theta Serpens), Albireo, Trapezium, Alcor-Mizar, Gamma Delphinus.
Mark, there are few people and probably even fewer instruments in the world that could cleanly split a 14.2 second pair at 8.5x.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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Mark9473
Carpal Tunnel
Reged: 07/21/05
Posts: 2519
Loc: 51°N 4°E
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Guess I should really hang on to these Swift 8.5x44 then... They indeed excell at double star work, it's just that this isn't one of my primary interests. Of course good resolution also helps at watching clusters (but magnification a lot more).
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Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50
WO Megrez II 80 FD
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12102
Loc: Cumberland, R I , USA42N71.4W
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Mark,
double star work does happen to be one of my primary interests. Actually I've studied double stars and resolution for several years. Never have I seen any instrument, let alone a binocular, that can perform such a feat. Yes, I've read other claims of such similar feats. But, years of observations and a knowledge of what others have done perhaps has left me with a healthy skepticism. What I find intersting here, is a nonchalant attitude regarding a world class observation without a second thought. So you'll pardon me if I question your observation, but at best from what I've seen, perhaps even 10x binoculars with the finest resolution can do no more than show this particular pair as clearly elongated. I have noticed it elongated in an 8, but have never seen it split in any 10. It is however easily split in a 12.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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KennyJ
Reged: 04/27/03
Posts: 9950
Loc: Lancashire UK
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< What I find intersting here, is a nonchalant attitude regarding a world class observation without a second thought. >
What I found just as interesting was the use of another word seldom seen here on this forum .
The word " nonchalant " .
It reminded me of the only song I can readily recall hearing it in .
Oddly enough , the following line is quite apt !
< Meanwhile I try to act so nonchalant
I can see a summer's night , the magic moon >
The song , a catchy old favourite of mine , which in September 1964 , I believe was the first ever UK Top Ten hit to feature a 12 string electric guitar , was called :
" When You Walk In The Room " by The Searchers .
Kenny
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Two eyes and a preference to use both
Zeiss 7 x 42 BGAT
Captain's Helmsman 7 x 50
Nikon 10 x 42 Superior E
Swift Audubon Kestrel 10 x 50
Helios 15 x 70 Observation
Strathspey 20 x 90
Televue 76 APO
Zeiss 85 Diascope
Helios 102 f5 refractor
Various eyepieces barlows tripods mounts etc.
Panasonic Lumix DMC - TZ5 digital camera
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GlenM
scholastic sledgehammer
Reged: 05/20/07
Posts: 785
Loc: 53° 36'N 2° 06'W
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Proper music Kenny or as the young people at the supermarket call it 'Christmas Music'.This must be an age thing.
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Glen
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CESDewar
GorillAstronomer
Reged: 01/16/05
Posts: 1679
Loc: Morganton, GA, USA
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Quote:
I dunno. I usually use the brute force method and use my 16X70 Fujinons on it. It is such an easy split with these. I could paint the bathroom with a Q-tip too, but what would be the point?
Well that same logic can lead you to question the value of looking through any amateur telescope - when it's obviously going to be vastly inferior to the Keck or the Hubble (I have actually heard some people express a disinterest in Astrophotography on that account). Or whether you sell off all your smaller telescopes when you finally get that 25" Dob.
It all depends on what your objective is. Big Dob owners often wonder why anyone bothers to observe DSO's in a 5" refractor, but that's because their sole interest is in eking out the maximum amount of detail. For me, that's only part of the equation. Part of it is learning the night skies, so I know where all the constellations, major stars and Messier objects are. Part of it is the fun of finding objects. Part of it is learning new starhops to find things more easily. Part of it is just the satisfaction of locating m4 even when it's only 12° above the horizon.
I find it just as much fun to catch a faint 10th Magnitude galaxy in my 4" scope as I do finding a faint 13th magnitude galaxy in my 15" scope.
I guess I look at double-stars as a challenge of visual acuity, a measure of how good the seeing is, how much better I'm getting with practice. On that basis, I would find it just as much fun trying to split a 14 arc-second double in 10x42 binoculars as I do trying to split a 1.1 arc-second double in my 5" refractor.
That being said, I'm taking out my 11x56 binoculars tonight to look at this, but my eyesight is not the best, so I'll be surprised if I see it split!
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Mark9473
Carpal Tunnel
Reged: 07/21/05
Posts: 2519
Loc: 51°N 4°E
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Quote:
years of observations and a knowledge of what others have done perhaps has left me with a healthy skepticism.
So you'll pardon me if I question your observation
Well, EdZ, I know what I saw, and I stand by what I reported. But I have other missions in life than to convince you.
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Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50
WO Megrez II 80 FD
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starramus
Pooh-Bah
Reged: 09/01/04
Posts: 1124
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Quote:
Well that same logic can lead you to question the value of looking through any amateur telescope - when it's obviously going to be vastly inferior to the Keck or the Hubble (I have actually heard some people express a disinterest in Astrophotography on that account).
I doubt very much splitting 100 Hercules at 10 power is going to generate an earth shaking paper in the journal Nature or some other publication of equal import.  I think we are mistaking self absorbed ego stroking for scientific contribution. Are we intensely scrutinizing the gyrations of gnats in this regard?
And I am one of those who would let NASA paint my bathroom with Hubble at the cost of billions rather than I expending precious thousands for a mole hill attempt at imaging in total redundancy with 10s of thousands of other amateurs. The reward/ cost factor is exceedingly low for what I would produce in mediocre images. It's already been done with equipment far advanced to what i would procure. Let us know how you do with the 11X56 binoculars.
Regards and clear skies,
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CESDewar
GorillAstronomer
Reged: 01/16/05
Posts: 1679
Loc: Morganton, GA, USA
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I spent some 30 minutes on 100 Hercules tonight.
Cutting to the chase....I got a clean split in my 11x56 Garrett's, but it did take quite some time to get them perfectly focussed to do this. These are great binoculars for under $100 shipped. Yes there is edge falloff, but the central sharpness is excellent.
By a clean split, I mean that I got the visual appearance of headlights - two tiny but definitely separated dots. It didn't happen every time I looked - and the Garrett's do not hold focus very well, so there was quite a bit of fiddling. I was actually quite surprised as my vision is average at best and my left eye is intentionally under-corrected by some 3+ diopters so I don't need reading glasses. This creates problems sometimes in getting both barrels to focus. Of course, I had the Garrett's mounted on a good tripod to do this.
Next I tried my 10x42mm - these Leica Ultra-Vids are obviously super-premium binoculars but the drop from 11x to 10x, in spite of the better optics, did not result in a split. I would describe it as a figure-8. Certainly close to splitting but at no point did I get that sensation of "headlights" that tells me it was a clean split. I spent another 10 minutes with them, but with no further gain. The Leicas have a much better edge and excellent contrast, but I have to say the Garrett's were a good match in the center.
Finally, I looked at it handheld in my 18x50 Canon's - that was an easy split and I expected that as I have seen tighter pairs in the 18x50's - on one occasion I definitely got 3 stars in the Trapezium with them. I do find it is important to focus these with the IS off and then engaging the IS to get the sharpest views.
Oh, and one final comment, I have a sneaking suspicion the 11x56's are slightly more than 11x - at some point I'm going to try and measure that more accurately, but it just seems like more than a 10% jump over my 10x42's.
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Edited by CESDewar (06/16/08 12:36 AM)
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ronharper
scholastic sledgehammer
Reged: 02/14/06
Posts: 876
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Thanks all you guys for getting caught up in this little saga and sharing your stories. Since my original post, I have split it nicely again, and failed again. I sure wish I knew what was going on. It seems unlikely that atmospheric stability would play a role in such a wide double star. I think the variability is more likely in myself.
Consider, I'm sitting there hunkered down in my chair, watching the star and my heartbeat, getting a hairline split a best. Then, all of a sudden, two dots!
I think my eyes are worse than some and better than some, really about average. If I do well, it's probably more due to good instruments than exceptional eyesight. Anyhow, there's no virtue nor vice in visual acuity or bat-blindness, as long as you can see well enough to enjoy the view, and not much to be gained by false bragging. Of greater interest to me than having the sharpest eyes on the block is understanding this process of seeing, getting better at it, and having more fun. Now, having the sharpest BINO on the block, well, for that I would gladly lie, cheat, and steal!
Thank you CES. Between you and the unnamed member, we've got a pretty good endorsement for the, what, not even $150?, 11x56.
By the way, the unnamed party who PM'd me with news of a split in his 11x56 has made clear that the bino was purely handheld, standing up with only a bit of back support. So, in addition to the obvious requirement of sharp eyes and a very well adjusted if rather cheap binocular, this raises the issues of musculoskeletal stability, and something that I NEVER see mentioned here, but seems of paramount importance in hand-held binocular observing, the eye's ability to follow a jittering image. Also, not curiously at all I thought, this same person expressed a great cognizance of an interest in this same issue, and offers the encouragement that practice, as in so many other things, works in handheld observing!
Who was the sharpest-eyed observer who ever lived? What is the gold standard to beat? There are telescopically-confirmed tales of people seeing Jupiter's moons, and Venus's phases, naked-eye. S. W. Burnham detected 0.4" elongations in previously unknown doubles with a 6" scope. Rev. "Eagle Eye" Dawes wrote down a criterion that has not been clearly beat. I can make out 0.5" elongations in a 5" scope PROVIDED I KNOW IT'S DOUBLE ALREADY, and I can agree with the Rev., but could never have written the definition down as he did. Of course, some of the greatest observers could see canali on Mars, a feat that has not been equalled in quite some time!
And then, we have Mark. He has raised some eyebrows by claiming to exceed the double-splitting acuity of anybody here. To his credit, he is perfectly consistent in his claims. In the review of his 8.5x44, there are some heavy-duty splits in there, with a bino widely revered for its central sharpness. In another review, he knocks the impressive WO 7x50 as not as sharp. I believe that the guy can just flat see. All you need is for an observer with astigmatism-free vision correctable to 20/10 in both eyes, ( I haven't looked for the bell-shaped curve of visual acuity, but I bet this is not so terribly unusual, and is TWICE as acute as normal vision), an excellent quality binocular like that old Swift, the unusual inclination to go out and bust a gut looking at close double stars, and the the fortitude to go public with it.
Onward! I split Cor Caroli tonight with my 10x50--faint companion, but overall easier than 100 Her.
Ron
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SaberScorpX
Post Laureate
Reged: 01/12/05
Posts: 4077
Loc: illinois, usa
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I see no reason to doubt Mark's report of ~120" VA.
I consistently pull 130-135" and have no problem believing there are 10-20% better VAs out there.
On a related subject, DS split (or any) reports might benefit if qualified as naked eye or corrected vision (CVA) obs. Splits made with corrective eyewear are obviously more a tribute to ones prescription than natural acuity. I don't think less of CVAs (some have had better-than-20/20 glasses made), but believe the distinction would lend an extra dose of reality to many readers.
Most know I'm not a big fan of tripod use.
While often a neccessary evil, the contradiction to the liberating principle of bino use has no doubt bothered me more than most over the years.
I can only credit this acquired handheld proficiency (HVA) to desire, endless sessions of practice at a wide variety of powers, and cumulative musculoskeletal adaptation.
10-20 minutes now and then is simply not going to do it.
Those wishing to put in the time might also be served well by extended warm-ups at higher powers, loosely analogous to taking practice swings with a ring weighted baseball bat.
By an ironic virtue of their narrow AFOV, higher powers also provide less off-axis 'distraction' when coaxing a split or increased detail.
Again, I don't think less of anyones tripod use for steadiness but can guarantee that an increased dependence will do nothing for developing handheld stability.
Directly specific to the topic, I have blacklined 100 Her at 11x handheld and at 10x mounted. It was not split (handheld or mounted) at 8x. I would not expect to bust it clean at 9x either.
Cor Coroli is relative cake and consistently reveals its colorful secret to me through handheld 8x40s (HVA ~156").
BTW, the 11x56 sales seem to be doing well. Mine is certainly getting alot of use.
Just wondering how much of its popularity is due to a Spinal Tap mentality
("But these go to 11...").
SJS
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12102
Loc: Cumberland, R I , USA42N71.4W
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Stuart,
when I tested the pre-release model of the Garrett 11x56, I found it was 11.75x.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12102
Loc: Cumberland, R I , USA42N71.4W
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Quote:
Directly specific to the topic, I have blacklined 100 Her at 11x handheld and at 10x mounted. It was not split (handheld or mounted) at 8x. I would not expect to bust it clean at 9x either.
Cor Coroli is relative cake and consistently reveals its colorful secret to me through handheld 8x40s (HVA ~156").
I consistently reach apparent separations in the range of 150-160 arcseconds, with all sizes of binoculars. I have had best readings with a few exceptional sessions down to 145 arcseconds.
Handheld observations generally at best reach no better than about 180-200 arcseconds, however, I have seen 100 Herc split with handheld Nikon SE 12x50s for a best ever apparent handheld separation of 170 arcseconds.
FWIW, I've identified this particular star as elongated with an 8x binoccular and I've identified closer stars as elongated with 10x binoculars. But some observers make a clear distintion between terms elongated, overlapped and cleanly separated.
It is quite common that overlapped pairs are often described by some observers as cleanly split. Stars overlapped by 20% will have deep notch indentations blackening fully 50% the width of the star points. These deep dark notches are often mistaken to blend to give the appearance of a continouos break. This is a fairly common misinterpretation described even by frequent double star observers.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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CESDewar
GorillAstronomer
Reged: 01/16/05
Posts: 1679
Loc: Morganton, GA, USA
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Quote:
Stuart,
when I tested the pre-release model of the Garrett 11x56, I found it was 11.75x.
Now that is very interesting. I added the note about my suspicions of it being more than 11x a few moments later when I realized it was obviously relevant. I was quite surprised at the difference between the Garrett's, where I could definitely see a split on more than one occasion, and the supposedly-much-better Leicas, which never showed a split in spite of my best efforts. But if this true of production models as well (and I suspect it is), it's certainly nice to know it's not just my imagination and that there is indeed a bigger difference in magnification.
The central sharpness is really excellent on these binoculars - of course it often is - one pays for edge sharpness, not center sharpness!
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ronharper
scholastic sledgehammer
Reged: 02/14/06
Posts: 876
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SJS,
Thanks for going public with your observations and your thoughts on those of others. I believe you are mistaken about what eyeglasses can do, however.
One cannot simply opt for eyeglasses giving better acuity than 20/20, unless he is somehow fortunate beforehand. Eyeglasses can correct for near and far-sighted focusing abnormalities, bringing best focus to the arbitrary distance of 20 feet, and also correct for simple cylindrical astigmatism. But that's all.
At this point, one is stuck with the inherent acuity of the eye that cannot be further improved. This would seem to include the small-scale shape irregularities of the eye lens, cloudiness of the cornea, lens, and interocular fluid, density and function of cone cells at the center of the retina, and the hook-up to the brain, which might be improved by practice.
Ron
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12102
Loc: Cumberland, R I , USA42N71.4W
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While it wouldn't be unexpected to find some of the best binoculars have some of the best resolution, central resolution is not necessarily dominated by the top brand binoculars. Here are some test results that prove such. These are the binoculars out of all 50-60 that I've tested that have shown (for me) the finest attainable resolution on axis. In order, leading up finally to the best measuered.
Nikon Action VII 8x40
Captain's Storm King 7x50
Captain's Helmsman 7x50
Fujinon FMT-SX 10x50
Bushnell Legend 8x42 Roof
Nikon 12x50 SE
Oberwerk Ultra 15x70
Celestron Regal 8x42 Roof
Nikon SE 10x42
Celestron Regal 10x42 Roof
Oberwerk Mariner 7x50
Pentax PCF WP II 8x40
Fujinon BFL 8x42
Nikon Action Extreme 8x40
William Optic 7x50 ED
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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KennyJ
Reged: 04/27/03
Posts: 9950
Loc: Lancashire UK
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< At this point, one is stuck with the inherent acuity of the eye that cannot be further improved. This would seem to include the small-scale shape irregularities of the eye lens, cloudiness of the cornea, lens, and interocular fluid, density and function of cone cells at the center of the retina, and the hook-up to the brain, which might be improved by practice. >
Ron ,
I am not qualifued to disagree with any of those points , nor have I any reason to .
However , with regard to improving acuity , I must mention again that anyone who happens to have TWO pairs of identical or very similar prescription DISTANCE glasses , ought to try wearing BOTH pairs at the same time .
It DEFINITELY improves my acuity , although I suspect that is entirely due to a doubling of the correction for astigmatism .
It's like selecting a TeleVue dioptrix lens that is 0.25 or 0.5 diopter STRONGER than is strictly necessary .
I've not actually tried the Dioptrix , but I've experimented with a selection of negative corrector lenses , and the results were consistent with wearing two pairs of glasses , one in front of the other .
I really hope you , or others , can and will give this a try , rather than try to prove me wrong by theoretical reasoning !
Regards and clear lenses
Kenny
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Two eyes and a preference to use both
Zeiss 7 x 42 BGAT
Captain's Helmsman 7 x 50
Nikon 10 x 42 Superior E
Swift Audubon Kestrel 10 x 50
Helios 15 x 70 Observation
Strathspey 20 x 90
Televue 76 APO
Zeiss 85 Diascope
Helios 102 f5 refractor
Various eyepieces barlows tripods mounts etc.
Panasonic Lumix DMC - TZ5 digital camera
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ronharper
scholastic sledgehammer
Reged: 02/14/06
Posts: 876
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Kenny,
When we've argued in the past about what we saw, the solution lay in the explaining. I totally believe you. Not having enough astigmatism that my glasses even correct for it, I'm afraid I can't try it for myself. If your prescription is correct, it sure seems like two pairs of glasses would bring your astigmatism past zero, to the point where it was as bad as uncorrected but of the opposite sign. Isn't that the way it seems to you, too? Obviously, my simple assumtions fail once again.
But, this is sort of reminiscent of telescopic observers' noting that they find the view sharper with, for example, a 12mm eyepiece and a 2x Barlow, than with a 6mm eyepiece alone, extra glass no matter. Not-simple stuff happens where sharp eyes meet optics.
Ron
SJS,
I, too, split Cor Caroli with with a braced 8x not long ago. This was in a heavily biassed maximum effort to prove my used Leica 8x42 Trinovid was a very sharp binocular, and that I had not wasted hundreds of dollars on a silly red spot. It took a few minutes, and all I had, but I got it. I confirmed it immediately at 10x. But for me, it was really tough.
Ron
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