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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1016
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V.A.- very interesting about owl's ears. Maybe this is relatable in some way to the fact that humans often *Word deleted by the CN gnaughties gnomes* their head relative to the three major spatial axes when something has caught their visual attention against a more general background (same thing happens when we hear something novel linguistically). Just goes to the fact that the brain uses the same interchangeable mechanisms to integrate all sense data in the end.
It also seems to suggest that perfect symmetry, while perhaps a desideratum for beauty, is not actually contrast-friendly informationally.
Jess Tauber
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ph2
super member
Reged: 11/28/05
Posts: 103
Loc: Aalborg, Denmark
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Quote:
Seems like this factor of 1.4 keeps coming up. Must be some truth to it.
If we assume our eye is not a perfect detector, but generates random noise just like a CCD or photographic film, then this factor 1.4 is exactly what you would expect in noise reduction by taking the average of two images
The improvement in signal to noise ratio (SNR) from stacking multiple noisy images is proportional to the square root of the number of images averaged. Stacking two images improve the SNR a factor 1.414.
I don’t know if it is valid to compare using two eyes with the action of taking the average of two CCD images, but it is an interesting idea.
The improvement in SNR would probably be seen as a more “clean” and “steady” image, making it easier to detect what you are looking for.
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KennyJ
Reged: 04/27/03
Posts: 10163
Loc: Lancashire UK
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ph2 ,
Good " scientific looking " name !
Brings to mind a cross between PhD and H2O :-)
Welcome to the discussion .
< I don’t know if it is valid to compare using two eyes with the action of taking the average of two CCD images, but it is an interesting idea. >
I agree this is an " interesting idea " , but I feel that it is partly because there is an over tendancy to compare man - made contraptions with what I will loosely classify as " god - given , natural phenomena " that there seems to be such a lack of understanding of these kind of matters .
In other words , mind - boggling and truly impressive as scientific and technological developments have been over the past century or so , they still pale into relative insignificance ( in my mind at least ) to the wonders of earthly biological forms , and to the tiny portion of the natural universe which we " know " ( a tiny bit ) about .
Regards , Kenny
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If everyone is thinking the same thing , no-one is thinking - General George S.Patton
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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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1016
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The word deleted by the CN gnaughties gnomes in my last post has a variety of meanings in the English language, including holding something up while under tension, and is the common name for a male fowl. Shame, shame! Next we'll be deleting 'bino' for its ambiguously negative implication toward people of alternative lifestyles!
Jess Tauber
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milt
sage
Reged: 09/13/04
Posts: 430
Loc: Arizona
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Quote:
I don’t know if it is valid to compare using two eyes with the action of taking the average of two CCD images, but it is an interesting idea.
The improvement in SNR would probably be seen as a more “clean” and “steady” image, making it easier to detect what you are looking for.
I like your analogy. However, I think the mammal brain does something beyond the average of two images; namely, it rejects non-correlated information. This is why you normally don't notice your nose, but when you close either eye it suddenly appears. Well, mine does, anyway. 
Now I'm going out to unconsciously correlate two images from my Highlander.
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Clear skies, Milt
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DJB
Pooh-Bah
Reged: 02/23/05
Posts: 1268
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Hey Bill,
Thank you. I agree that 2% may very well be a correct estimation. BUT, since one's eye(s) respond in a log fashion rather than a linear fashion, I would hesitate to sign my J.H. at the bottom--you know what I mean.
However, I will agree with your professor's judgement. Good stuff, Bill.
Regards,
Dave.
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BillC
on a new path
Reged: 06/04/04
Posts: 2111
Loc: Washington, USA
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DJB:
Thanks for your kind words.
I certainly understand what you mean. Even so, I do not mind having my name associated with my comments. First, I stand by them. Secondly, I do not mind being proven wrong. I want to promote accuracy in the dissemination of optical knowledge. If I wrote for ego, I would be trading letters with friends in the National Writers Union. I just want folks to think a little deeper.
When the thread started, it was postulated that the second objective of a bino increased the LIGHT GRASP of a bino by 40%. I knew this was bull, and so stated. Then when I started talking in terms of neurology and physiology the tone changed to include phrases like “Binocular Summation.” Ah, then we were getting somewhere. I never said that the EFFECT of two objectives was not substantially better than one. I merely stated that the reason was not a 40% increase in LIGHT GRASP. Had that issue not been addressed, would newbies passing the thread not come away with inaccurate information?
As stated, it really doesn’t matter to me. The causes related to the results go WAY beyond my understanding of optics, optical engineering and ophthalmology. However, I think that if we are going to spend time kicking around such functionally useless information, we should see to it that the functionally useless information we kick around is as ACCURATE as possible. Is that fair?
You state that our eyes respond in a “log fashion.” But, do we really know that? I certainly do not know. What I do know is that the net is full of assumptions and old wives tales that have been elevated to the level of fact.
As far as me being proven wrong on whatever subject, well, I am ALL FOR THAT, as long as it adds to the propagation of more accurate information. Besides, I am thoroughly accustomed to looking stupid; I’ve reared three teenagers.
Cheers,
Binocular Bill
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William J. Cook, Chief Opticalman, USNR-Ret.
Founding Editor, Amateur Telescope Making Journal
20-year vet. of Captain's Nautical Supplies, Optics Dept. Mgr.
Optics Machanic, WG11-3306, Ft. Lewis, Tacoma,WA
Yata, Yata, Yata . . .
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refractory
Pooh-Bah
Reged: 02/05/05
Posts: 1016
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Speaking of not normally noticing your nose- is binocular correlative vision equally enhanced in all areas of the visual field? I mean that if your nose is normally present in the south central part of the field, do we see things there brighter or dimmer than otherwise might be the case?
If so is this purely experiential, so that when we look into binos the effect disappears, or is it hard- (innate) or soft- (learned) wired, so that when we look into binos the effect remains?
I know that we compensate for our visual blind spots- but since these are in different places in the two eyes does binocular vision also help us to create a seamless experience as well? But less/more bright?
Now I'm all crosseyed and confused!
Jess Tauber
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BillC
on a new path
Reged: 06/04/04
Posts: 2111
Loc: Washington, USA
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Just be thankful you are not a politician. Many of them have blind spots that are directly in front of them.
Cheers,
Bill
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William J. Cook, Chief Opticalman, USNR-Ret.
Founding Editor, Amateur Telescope Making Journal
20-year vet. of Captain's Nautical Supplies, Optics Dept. Mgr.
Optics Machanic, WG11-3306, Ft. Lewis, Tacoma,WA
Yata, Yata, Yata . . .
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BillC
on a new path
Reged: 06/04/04
Posts: 2111
Loc: Washington, USA
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Post deleted by BillC
--------------------
William J. Cook, Chief Opticalman, USNR-Ret.
Founding Editor, Amateur Telescope Making Journal
20-year vet. of Captain's Nautical Supplies, Optics Dept. Mgr.
Optics Machanic, WG11-3306, Ft. Lewis, Tacoma,WA
Yata, Yata, Yata . . .
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pcad
Carpal Tunnel
Reged: 01/17/05
Posts: 1501
Loc: Connecticut
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Refractory,
Some aspects of binocular vision only develop after birth. Children with crossed eyes or wildly differant rx's for each eye are at risk for amblyopia, aka lazy eye. Stereopsis, binocular depth perception, is definately affected in these cases.
With stereopsis, it isn't really learning per se, but more an abnormal developmental issue.
I don't know if what we are calling binocular summation is also affected.
BTW, even though we aren't normally aware of our physiologic blindspots, they are easily demonstrated.
Peter
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Peter
Telescopes 25 - 318 mm
Binoculars 15 - 88 mm
Microscope 50x - 1000x
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DJB
Pooh-Bah
Reged: 02/23/05
Posts: 1268
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Hi Bill,
Thanks again for your great response. I'll just say that the 40% blew me way away, too!
I have to agree that there is much rubbish out there in web land. I guess that is the reason I still like reference books and published papers. Interesting topic, tho.
Regards,
Dave.
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