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SaberScorpX
Post Laureate
Reged: 01/12/05
Posts: 4116
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: 12341
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: 12341
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: 1742
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: 964
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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: 12341
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: 10031
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: 964
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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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Mark9473
Carpal Tunnel
Reged: 07/21/05
Posts: 2614
Loc: 51°N 4°E
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Quote:
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 .
Kenny, I've never worn distance glasses, but what I notice when using my reading glasses to look at something distant, is that it increases the magnification. Could that be the cause of what you describe?
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Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50; Orion 15x63
WO Megrez II 80 FD + Baader 90° T2 Amici
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KennyJ
Reged: 04/27/03
Posts: 10031
Loc: Lancashire UK
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Ron ,
Thanks for your understanding comments .
Your " sub - zero " astigmatism description fits my visual experience rather well !
Mark ,
Wearing reading glasses when looking through binoculars increases the magnification for me , too -- but that is not the same at all to what I'm describing .
In fact , if anything , strange as it may sound , it's as if putting the anti - astigmatism lenses in series , slightly REDUCES magnification , yet significantly increases " sharpness " .
Unfortunately , when it comes to optics , there is no such thing as " sharpness " in the vocabularly of the technically correct !
Kind regards
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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Fiske
Carpal Tunnel
Reged: 03/14/04
Posts: 2057
Loc: Missouri / United States
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Not that I have any light to add to the dicussion about splitting 100 Hercules at lower magnifications, but I remember talking about this double a few years ago during the fall when I couldn't easily observe it, so I was pleased by this reminder that I hadn't checked in on it with binoculars.
I gave it a try last night and found it nicely split in tripod mounted 12x50 SEs. I could not split it with the same bino hand held. Nor could I split it with 10x50s or Nikon 8x42 LX binos, either hand held or on a tripod. My 10x50s are Nikon Lookout IVs that have been through a lot and aren't that great, unfortunately. I'm contemplating upgrading them to a Nikon 10x42 EDG when they are available.  I have heard Nikon is discontinuing the 10x42 LX, second series, which I think is lunacy, but that's corporate executives for you...
It was a beautiful double in the 12x50s on the tripod, though. A celestial destination I look forward to visiting again.
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Fiske Miles
Nikon 8x42 LX / 12x50 SE Binos
Mini Borg 60ED, TV-101, AT80Ach, XT-8, C11/CI-700, 22-Inch Dob
Way too many Nagler eyepieces
http://www.fiskemiles.blogspot.com/
www.fiskemiles.com
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Denis
sage
Reged: 12/24/05
Posts: 204
Loc: Rennes, France
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Some binocs observation the last two evenings.
With the canon 10x42 IS, 100 her was cleanly split and I try the perl escape 8x42 monted on a tripod, but just see it elongated.
Due to the easy split with the canon, I hoped a split with the 8x42 but no means.
I also try 40/41 Draco, a nice pair separated at 19". The 8x42 split it cleanly without difficulty.
I could say I have about the same view of 40 Draco in the 8x42 than 100 Her in the canon 10x42.
Denis
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Canon 10x42 IS binoculars.
Meade sc 4" on homemade fork equatorial mount.
homemade 10" an 14" dobsonian
Nikon photogear.
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rookie
sage
Reged: 01/14/06
Posts: 252
Loc: St. Petersburg, FL
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Thanks to everyone who contributed and posted to this thread as I have learned a lot from all of you. I've taken up the challenge and have gone out on many nights to look at this double. The first night I was certain that I saw it cleanly split with my Regal 10x42's and more like an oval with my Ultima 9x63's. It was a cake-walk with my BT80's at 26x. Since that night I have not had the same experience. The full moon came and went and we have not had good clear skies here for the past 2 weeks and it's murky appearance with the 10x42's is that of a single star. I also learned from the many descriptions describing double star viewing and wonder if I did not see a co-joined rather than cleanly split double the first night with my 10x42's.
It seems to me that this double star's separation is conditionally viewable at lower powers. Many factors come into play:
personal acuity (I had Lasik surgery and have 20/15 vision in my left eye)
dark sky / high contrast
steady upper atmosphere
elevation
mounted / high-quality optics (no experience with IS bino's)
level of fatigue
wine vs coffee 
achieving dark adaptation
patience
good ~really good~ focus
stubbornness or perserverance (not sure)
I also am a believer in logging observations and developing a reviewable history. I just helps me learn and remember.
There is a remarkable wealth of knowledge in this forum. Thanks for helping those of us with on the front end of the learning curve! 
Please give us more challenges!
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Shirley
Celestron CPC 800XLT
G0 BT80~45degree; Fujinon 16x70 FMT-SX
Celestron Ultima 9x63 & Regal LX 10x42
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Mark9473
Carpal Tunnel
Reged: 07/21/05
Posts: 2614
Loc: 51°N 4°E
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Shirley, in your list one of the items is "achieving dark adaptation". I actually believe it's the opposite as long as the target is bright enough. Dark adapted vision is just less sharp for me.
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Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50; Orion 15x63
WO Megrez II 80 FD + Baader 90° T2 Amici
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12341
Loc: Cumberland, R I , USA42N71.4W
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I'd sort of agree with Mark. For doubles, dark adaptation isn't as critical as for faint extended objects.
From Shirley's criteria
Quote:
personal acuity (I had Lasik surgery and have 20/15 vision in my left eye)
dark sky / high contrast
steady upper atmosphere
elevation
mounted / high-quality optics (no experience with IS bino's)
level of fatigue
wine vs coffee
achieving dark adaptation
patience
good ~really good~ focus
stubbornness or perserverance (not sure)
I also am a believer in logging observations and developing a reviewable history.
I would say the most important are
personal acuity
steady upper atmosphere
mounted / high-quality optics
level of fatigue
wine
patience
good ~really good~ focus
perserverance
logging observations and developing a reviewable history.
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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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ronharper
scholastic sledgehammer
Reged: 02/14/06
Posts: 964
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From what I've read about vision, dark adaptation is irrelevant to acuity. Dark adaptation increases the sensitivity of the rod cells, which dominate the retinal region away from the center, ie, averted vision. The central region, or fovea, is populated densely with cone cells which provide sharp vision.
Ed, I never realized that wine was that important. This is great news. I sometimes celebrate a difficult split with a toast to myself, and another to my binocular (sometimes separate toasts to the individual telescopes, the coatings, prisms, etc.), but maybe I should try a good slug before I go out!
Ron
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12341
Loc: Cumberland, R I , USA42N71.4W
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I was out last night tested a few 7x50s. Also had with me my 10x50 Fujinon. While I could easily tell 100 Her was a double in the 10x50s, I could never call it completely separated. Notched? yes. Separated? no.
With the 7x50s I could not even guess at dupliticty.
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: 12341
Loc: Cumberland, R I , USA42N71.4W
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Out again last night with several binoculars, 100 Herc became a target. I had a friend over so we tried a few binocs. I saved the 15x70s for last.
We started with the Vixen Foresta 7x50. I could tell which star was 100 Herc only because I knew its location, but neither of us could even see elongation in the pair. I would say perhaps 100 Herc looked like it might be slightly misshapen in a 7x50, but if you didn't know it was a double you would not see it as anything more than a single star.
Next we tried the Celestron Regal LX 8x42. At least in the 8x42, we both could see elongation. However on 2 out of 4 guesses, we guessed wrong on the orientation of the pair. The Regal is very close to 8x, it's actually 8.1x. So at 8.1x we were able to guess at the orientation of the pair. That's an apparent size of 115 arcseconds. I've had 4 other binocular observations of record where I've been able to declare orientation of a pair at apparent sizes between 113 and 118 arcseconds, so this fits right in.
Both the Vixen 7x50 and the Regal 8x42 are two of the best binoculars I've tested for resolution, in the top 10 of all binoculars I've ever tested.
At this point we took a look thru the 15x70s and could see which guess for orientation was right and which was wrong. the 15x70 allowed seeing the split easily, but the stars were not focused nearly as tight.
Finally, I tried with my Fujinon 10x50. This is actually 10.4x.
My friend was not able to confirm a split with the 10x50, but did see two components. With very careful focusing and careful attention to detail, I was able to see the split between the two components. That's a very good observation for me, an apparent resolution of 148 arcseconds. I can count the number of times I've gone under 150 on one hand.
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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RichD
super member
Reged: 11/08/07
Posts: 170
Loc: Derbyshire, UK
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Are you calling that a definite separation edz, or as in your above post able to see it notched only?
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Clear skies
Rich
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12341
Loc: Cumberland, R I , USA42N71.4W
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Quote:
Are you calling that a definite separation edz, or as in your above post able to see it notched only?
As I posted, from my observation last night
Finally, I tried with my Fujinon 10x50. This is actually 10.4x.
... With very careful focusing and careful attention to detail, I was able to see the split between the two components. That's a very good observation for me, an apparent resolution of 148 arcseconds. I can count the number of times I've gone under 150 on one hand.
I've still never seen it clean at 10 power. I'll pick out one of my even 10 power binocs with good resolution and give it a go.
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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