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Two Mechanisms of Vision: Ambient Vision and Focal Vision (3 Viewers)

Canip, relax, click here. And I thought the excitement had now died down. :)

Adding in edit:

In post #74 there's a link to a lengthy, very thorough, article on the word in British Birds. The foll. is an extract.

It omits Switzerland, but does include the countries of origin of its three main languages.

"We have enquired about the ornithological use of 'jizz' in other European countries. None of our informants said that 'jizz' was not used in their country, though it was said to be very rare in Hungary. Birdwatchers in Denmark, France, Italy, Norway, Poland and the Netherlands use 'jizz' and appear to have no equivalent word in their own languages; those in Hungary, the Czech Republic, Germany, Spain, Finland and Sweden use both 'jizz' and one or more native words or expressions for the same thing. Some informants said it was used more by experienced or 'hard-core' birders..."
 
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Omid, thank you for your responses.

The other paper by Land you attach is particularly useful to me.

There is a lot for me to digest in this matter.

By "information input from panning" I meant "relevant information input..." Sorry that was not precise enough for you!
 
Identification by „jizz“?:oops:
What am I missing?
A lot ... :cool: In birding "jizz" refers to the overall impression of a bird, its shape, posture, flying pattern, and general behaviour. "Jizz" is used to describe distinctive characteristics that allow identification of a bird from a distance or in poor viewing conditions. The concept of "jizz" is about capturing the unique combination of features that make a particular species recognizable, even if details like plumage color or markings aren't clearly visible. It's a holistic approach to bird identification that relies on experience and familiarity with different bird species.

Hermann
 
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I 'find' birds in three ways.
Mostly by staying still, gazing, and seeing their movement.
And by slowly scanning(i.e. panning) along seashore, scrape and fences/walls. If there are numerous birds then it is often the character (jizz) of one that makes it stand out. While the panning may be slow and smooth, my eyes still noticeably 'jump' a little to adjust to the lateral movement.
However tracking a flying bird seems effortlessly smooth both for movement and focus. Presumably the brain compensates?

Occasionally I will look for soaring gulls and buzzards beyond my vision over the wide farmland vista behind my house. Rather than panning a featureless sky I scan one area, move the binoculars right (or down) and scan another area, move again...much as you might move the binoculars from one tall pylon to the next.

And when I hear a twittering skylark I pan vertically upwards in the direction of the noise.
 
Summary and Invoice

Thank you BirdForum members for your continued interest in this thread. So far, I have explored a plurality of fundamental subjects including:

Post # 1: Two Mechanisms of Vision (Ambient and Focal)
Post # 5: Neural Mechanisms subserving Ambient and Focal Vision
Post # 10: An alternative approach for estimating low-light "detection performance" of binoculars
Post # 17: Definition of Salience and that fundamental stimulus to vision is "motion"
Post # 18: The impossibility of optically magnifying "space"
Post # 24: Effect of optical magnification on perspective
Post # 31: Visual tracking of a moving animal (smooth pursuit)
post # 38: Why you should not pan with your binoculars - 1 (Optokinetic Nystagmus)
Post # 45: Binoculars create a false visual ground, disturbing our sense of balance and posture
Post # 57: Preventing vertigo by adding a "fixation target" to a moving visual background
Post # 69: Why you should not pan with your binoculars - 2 (fixation and saccade strategy)
Post # 77: Spotting wildlife is easier without binoculars (using our natural Ambient Vision)

To write each of the above posts, I have spent at least 2 and more typically 3 hours of my professional productive time. I often edit and re-write my posts several times to make sure they are accurate and consistent. I also add video clips and cite relevant scientific literature when possible. Given the value of my time ($320/hour) and the estimated time I have spent writing the above posts (24 ~ 36 hours), the total value of the effort I have put into creating this thread up to this point is between $8,000 to $12,000. :eek: :oops:

Omid:
I sure find your explanations of how the visual system works fascinating. But I'm not sure how these insights can be applied to birding. In other words: I don't know what the practical implications for birders are - if any. And it's the practical implications I'm most interested in.

Great question and it's time for me to clarify: My intention in creating this thread was introducing lesser-known concepts of human vision to those members who have a scientific background and an interest in fundamental design aspects of binoculars. In particular, I hope Dr. Holger Merlitz becomes interested in this new way of looking at "vision" and follows it independently on his own with the hope of coming up with fundamentally new concepts for binocular design. Binocular design is not a dead or finished subject. It is dead if we keep thinking along the traditional lines of "more field of view" or "less aberration" or "lighter weight" or a this or that type of prism. But if we follow the line of thought that I am presenting here, new possibilities and configurations will emerge. I have a few ideas in mind, and I will present them in due time as we go forward. Do you have any ideas yourself? If not, then maybe you and Holger should go to a German bar and drink together while watching the below video until you come up with some innovative idea ;)


The rifle sight shown in the video is a joint innovation by me and Mr. Hermann Theisinger (former head of product development at Carl Zeiss Sports Optic).

If independent thinkers don't innovate, the premium binocular industry will die (in fact, its dead already). There is zero hope that corporations (Zeiss, Swarovski, Leica or Nikon or any other manufacturer) will come up with something new and interesting. They will continue doing what they have done in the past thirty years: adding innovative two-letter combinations to binocular names :p(y)(y)

So, that's why I have created this thread: to reinvigorate the field of binocular design. If we didn't come up with a new idea, at least these scientific concepts will remain here for others to read and learn from.

Cheers,
-Omid
 
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Lovely, but what are the salient points of the design?

Novel perhaps, but how is it progressive?

Maybe I’m just thick.
 
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So, what do you do, taking into account your insights into how the visual system of humans works?
This is a good question, so it seems likely not to be answered. It's not clear that Omid uses binoculars for anything. A sandpiper among dunlins isn't going to stand out the way a cartoon fish does among rest-room signs, and there's no way an instrument could get it to short of AI processing of a digital image, which of course no longer has anything to do with human vision. (It may be worth noting that in human evolution there was no need to distinguish sandpipers from dunlins, especially at a distance.) This "exploration" seems to be concerned with problems that users of binoculars aren't having, which explains why R&D departments haven't been occupied with them.

Given the value of my time ($320/hour) and the estimated time I have spent writing the above posts (24 ~ 36 hours), the total value of the effort I have put into creating this thread up to this point is between $8,000 to $12,000.
But a good laugh is priceless!
 
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For some more detail, a quick search shows US patent US20210215458A1, published 15th July 2021 (see the attached copy).


The Abstract states:
'To enable a user to quickly adjust power ranges of a scope for firearms, a scope may be provided with a primary sight having a primary sighting line and a secondary sight having a secondary sighting line. The primary sight may include a plurality of optical elements disposed within the first housing and an elevation adjustment mechanism for adjusting a zeroed-in position of the primary sight. To prevent impedance of the secondary sighting line, the elevation adjustment mechanism may be located laterally of the primary sight rather than in the conventional position above the primary sight.'


And the Summary:
'Advantages of One or More Embodiments of the Present Invention
[0005] The various embodiments of the present invention may, but do not necesarily, achieve one or more of the folowing advantages:
[0006] the ability to provide a scope with a tilted eye piece;
[0007] the ability to mount a secondary sight to a scope;
[0008] the ability to switch between two optical systems with only minimal head and/or eye movement;
[0009] provide an elevation adjustment for a primary optical sight that does not interfere with or impede a line of sight through a secondary optical sight.
[0010] These and other advantages may be realized by reference to the remaining portions of the specification, claims, and abstract.'


Internal View.jpg

- - - -
In the video the concept is shown as a 1x reflex (mirror) optic, mounted above a 4x telescopic sight, that has the addition of 2 prisms.
The use of prisms in the telescopic sight enables the angled optical path, so at the point of optimal eye relief for the image and reticle
of the telescopic sight, there is close alignment of the reflex sight dot.
(In contrast to conventional telescopic sight and binocular optics, the image and reticle of 'red dot sights' typically have non-critical eye relief.)


John


p.s. An alternate image from the video. It makes clear that the use of prisms results in a shorter overall length than otherwise for the telescopic sight:

Video.jpg


For comparison, a diagram from Swarovski of a typical telescopic sight. It shows the greater length from the use of lenses to invert and reverse
the image from the objective, so that it's correctly displayed to the eyepiece (the lenses don't fold the light path the way that prisms do):

Telescopic sight optics.jpg
 

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For some more detail, a quick search shows US patent US20210215458A1, published 15th July 2021 (see the attached copy).
John

Good job John! You found my colleague's abandoned application which is based on a modification of the Abbe-Konig prism surface angles. For your information, the actual patents covering this invention are US Patent No. 10,254,083, US Patent No. 9,644,920 and US Patent No. 9,435,611.The key innovation is bending the exit pupil upwards using a wedge prism positioned after the eyepiece.

This sight offers 1X view (Ambient Vision, both eyes open) and 4X magnified view (Focal Vision for precision aiming) to the shooter with a simple change of gaze direction. Furthermore, the red-dot sight acts as a viewfinder for the magnifying sight: by putting the red dot on a far target, the target will automatically appear inside the field of view of the magnifying optics (no need to find it using the small FoV of the magnifying sight).

1743121728026.png
 
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Summary and Invoice

Thank you BirdForum members for your continued interest in this thread. So far, I have explored a plurality of fundamental subjects including:

Post # 1: Two Mechanisms of Vision (Ambient and Focal)
Post # 5: Neural Mechanisms subserving Ambient and Focal Vision
Post # 10: An alternative approach for estimating low-light "detection performance" of binoculars
Post # 17: Definition of Salience and that fundamental stimulus to vision is "motion"
Post # 18: The impossibility of optically magnifying "space"
Post # 24: Effect of optical magnification on perspective
Post # 31: Visual tracking of a moving animal (smooth pursuit)
post # 38: Why you should not pan with your binoculars - 1 (Optokinetic Nystagmus)
Post # 45: Binoculars create a false visual ground, disturbing our sense of balance and posture
Post # 57: Preventing vertigo by adding a "fixation target" to a moving visual background
Post # 69: Why you should not pan with your binoculars - 2 (fixation and saccade strategy)
Post # 77: Spotting wildlife is easier without binoculars (using our natural Ambient Vision)

To write each of the above posts, I have spent at least 2 and more typically 3 hours of my professional productive time. I often edit and re-write my posts several times to make sure they are accurate and consistent. I also add video clips and cite relevant scientific literature when possible. Given the value of my time ($320/hour) and the estimated time I have spent writing the above posts (24 ~ 36 hours), the total value of the effort I have put into creating this thread up to this point is between $8,000 to $12,000. :eek: :oops:



Great question and it's time for me to clarify: My intention in creating this thread was introducing lesser-known concepts of human vision to those members who have a scientific background and an interest in fundamental design aspects of binoculars. In particular, I hope Dr. Holger Merlitz becomes interested in this new way of looking at "vision" and follows it independently on his own with the hope of coming up with fundamentally new concepts for binocular design. Binocular design is not a dead or finished subject. It is dead if we keep thinking along the traditional lines of "more field of view" or "less aberration" or "lighter weight" or a this or that type of prism. But if we follow the line of thought that I am presenting here, new possibilities and configurations will emerge. I have a few ideas in mind, and I will present them in due time as we go forward. Do you have any ideas yourself? If not, then maybe you and Holger should go to a German bar and drink together while watching the below video until you come up with some innovative idea ;)


The rifle sight shown in the video is a joint innovation by me and Mr. Hermann Theisinger (former head of product development at Carl Zeiss Sports Optic).

If independent thinkers don't innovate, the premium binocular industry will die (in fact, its dead already). There is zero hope that corporations (Zeiss, Swarovski, Leica or Nikon or any other manufacturer) will come up with something new and interesting. They will continue doing what they have done in the past thirty years: adding innovative two-letter combinations to binocular names :p(y)(y)

So, that's why I have created this thread: to reinvigorate the field of binocular design. If we didn't come up with a new idea, at least these scientific concepts will remain here for others to read and learn from.

Cheers,
-Omid


Hi Omid,

I cannot immediately see how the insights of this thread regarding panning and its effects on vision could trigger innovations in the design of conventional binoculars. With digital binoculars they might: Having software and plenty of computational power, the binocular could possibly remove the panning motion from the image and only preserve the peculiar motions of objects in the field. This would be some sort of extension of the image stabilization philosophy to large angle motions. The image would then have to be updated twice or trice a second, to mimic the action of saccades during normal vision. Perhaps ...

Your innovative gun sight could obviously be useful as a finder scope in astronomy, too.

Cheers,
Holger
 
The concept of "jizz" is about capturing the unique combination of features that make a particular species recognizable, even if details like plumage color or markings aren't clearly visible.
Is it more typically invoked when a bird has been seen in focal vision but not ideally well or long enough, or seen only peripherally?


This sight offers 1X view (Ambient Vision, both eyes open) and 4X magnified view (Focal Vision for precision aiming)...
So when you say "quickly adjust power ranges of a scope" you're not talking about zoom, just alternating between a magnified and non-magnified view. I have no experience with rifles, but isn't 4x a bit low, and does the concept work equally well with higher magnifications? Now we see how panning with magnification is to be avoided... but how does this solve the initial problem of finding a target that's not easily detected with unaided vision?
 
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Is it more typically invoked when a bird has been seen in focal vision but not ideally well or long enough, or seen only peripherally?
In focal vision, but not just when the hasn't been seen ideally well or long enough. You can always identify birds by jizz, and I find I do. Birds seen peripherally - yes, identification by jizz comes into this as well, for instance when I decide whether to look at something closely. Say, I'm looking at a bird of prey and notice another bird of prey somewhere in the background. Its jizz (for instance the way it flies) helps me decide whether I look at it more closely.

Hermann
 
Visual angle does not determine perceived object size

In many textbooks on optics, the perceptual effect of microscopes and telescopes is explained as "magnification" because the visual angle subtended by objects will be magnified if they are viewed through a telescope or a microscope. A magnification factor M > 1 (which is optically calculated) is then assigned to the instrument.

Visual_Angle.png

Now, take a look at the picture below:

cars.jpg

In this picture, all three cars subtend the same visual angle (use a ruler to measure them!). However, we perceive the top car as being substantially bigger. How could this be? What makes the top car appear magnified?

We see the cars in the picture at different sizes because our Focal Vision puts objects in perspective, i.e. sees object sizes relative to their surrounding environment. Surrounding objects can create a visual scale for size of an object independently of the visual angle. In human vision, an accurate percept of actual size is constructed based on multiple factors: some are provided by Ambient Visual System based extra-retinal factors (e.g. angle of gaze with respect to the ground and our own height) and some are calculated from the retinal image itself by the Focal Visual System (using laws of perspective for sure but also possibly using motion parallax as well as knowledge from past experience).

Size constancy in biological vision
In the natural world, this scaling process is amazingly accurate so that instead of judging objects as changing size as they move around (law of visual angle), our conscious (focal) vision will perceive objects' sizes as constant. This perceptual size constancy works well up to a radius of ~30m which psychologist refer to as Extra Personal Action Space. We, i.e. no-psychologists, can simply call this space a stone's throw from where we are! :) Beyond a stone's throw, our ability to correctly perceive sizes and distances will diminish, and things will simply appear as being "small" and "far away".

Different (and more accurate) size constancy mechanisms operate within the Peri-Personal Space. This is the space directly surrounding our body where we can act and interact with objects directly. Within the Peri-Personal space, Ambient Vision has extremely accurate body-scaled knowledge (mental maps) of directions, distances and sizes of objects (although it might not know what those objects are). This knowledge is "unconscious" meaning that we are not usually aware of it. This unconscious knowledge (mental map) is primarily used to control and guide our hands and, secondarily to scale our conscious perception of near objects towards their constant physical size.

Thanks to the constancy mechanisms, our focal vision recreates a near orthographic view of objects and scenes within the realm of Peri-Personal and Extra Personal Action Spaces. This is to say, our visual experience is more closely approximated by the orthographic projection shown on the right side in the below diagram as opposed to the geometrically correct "perspective projection" depicted on the left side:

Orthographic.png

Now the question arises as to how the artificial optical magnification M created by binoculars affects our size constancy mechanism? In previous posts (#18 and #24), I argued that binoculars tend to create a feeling that the observer has moved closer to the object wile size remains nearly constant. But this question needs to be explored more fully. The answer can't be that simple in all scenarios :rolleyes:

-Omid
 
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It's not the fact that we're looking at this image on a screen that disrupts the "natural processes of vision", but the fact that the image itself is an artificially constructed joke, which is sensed so quickly that one knows one's visual processes are in fact working. One isn't making judgments of perspective here because that has been deliberately ruined; one just tries instead to correct the error by estimating the correct original size from nearby objects. As to how one would "reach out" here, one also knows one can't grasp images, or cars with one's fingers. (If you want to illustrate a natural process, you need to start with a natural example.)

This sort of magical mystery tour (":p :p") cannot serve your alleged purpose. It's too difficult to guess what the sources you're drawing from (and no longer even mentioning) might actually have said.

Still awaiting answers to previous questions also.


Edit: post #93 has now changed completely... one can begin to see what the car photo is meant to do, by removing the confusing background (see below). Yes, the car images are the same size, and the way they've been stacked creates an illusion of perspective. But what this has to do with the rest of the material referred to remains unclear, as does its relevance itself ("orthographic projection", "scaling of size", etc).
 

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Ambient vision runs automatically beneath the level of consciousness. This visual system
  1. is color blind
  2. has wide field of view (mediated by the peripheral photo-receptor cells of the retina)
  3. has low spatial resolution
  4. works day and night
  5. uses a "body centered" frame of reference
  6. detects metric (absolute) size and direction of objects that constitute space at large
  7. has extremely fast reaction time (direct access to certain muscles)
Can be 'replayed' to build a 'stacked' colour image of an unseen object that moved swiftly through the field of vision in the preceding seconds - if you were alerted to that 'something' (but kept perfectly still for several seconds while the image 'developed') moving at speed in close proximity, ~3 inches through to ~40 feet.
 
I think we can guess where the tour is heading now: bringing moderately distant objects apparently 8-10x closer unnaturally places them in our Personal Action Space (if not Pre-P considering the location of the virtual image) thereby creating such disturbing problems that it's harmful not just to pan, but to use binoculars at all. Except it's hard to tell whether there's anything to this concept of a distinct PAS in the first place, not to mention its application to binoculars; a quick search turns up only discussions of travel and social interaction.

And of course, no one reports experiencing such difficulties anyway. Anyone might feel some frustration with the incremental development of binoculars today and be eager to imagine some more exciting improvement, but chasing imaginary problems won't produce it. And that's a peculiar sort of frustration, when one should instead appreciate how very good one's bins already are.
 
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I think we can guess where the tour is heading now: bringing moderately distant objects apparently 8-10x closer unnaturally places them in our Personal Action Space [...] thereby creating such disturbing problems that it's harmful not just to pan, but to use binoculars at all. Except it's hard to tell whether there's anything to this concept of a distinct PAS in the first place, not to mention its application to binoculars [...]

And of course, no one reports experiencing such difficulties anyway. Anyone might feel some frustration with the incremental development of binoculars today and be eager to imagine some more exciting improvement, but chasing imaginary problems won't produce it.
Perfect summary. The acid test for a theory that predicts certain outcomes is the reality. If the predicted outcomes are not observable in reality, the theory is either false in its entirety or needs to be modified (if possible).

Hermann
 
Perfect summary. The acid test for a theory that predicts certain outcomes is the reality. If the predicted outcomes are not observable in reality, the theory is either false in its entirety or needs to be modified (if possible).

Hermann
Hear, Hear!
 
Perfect summary. The acid test for a theory that predicts certain outcomes is the reality. If the predicted outcomes are not observable in reality, the theory is either false in its entirety or needs to be modified (if possible).

Hermann

I am not so sure whether the perspective effects (and the compensation done by our vision) are really irrelevant here. Magnification affects the perception of perspective, and this may in turn affect the size we believe an object must have. Possibly, this happens all the time but we are used to it since we have been using our binoculars so many times before. I think it is interesting to learn about these quirks of human vision, regardless whether this eventually leads to better binoculars or not.

Cheers,
Holger
 
I am not so sure whether the perspective effects (and the compensation done by our vision) are really irrelevant here. Magnification affects the perception of perspective, and this may in turn affect the size we believe an object must have. Possibly, this happens all the time but we are used to it since we have been using our binoculars so many times before.
This is actually an old hat. Peter J. Grant wrote an excellent paper in British Birds on "size illusion" and its implications for bird identification way back in the 1980s. I remembered reading it many years ago and discussing it with some birder friends. I found it in my library, but it's also available online as a pdf: https://britishbirds.co.uk/sites/default/files/pdf-store/V76_N08_P327_334_A095.pdf Worth reading (like anything Peter wrote)!
I think it is interesting to learn about these quirks of human vision, regardless whether this eventually leads to better binoculars or not.
True. Even though I'm not that much interested in "better binoculars" as in the implications for birding with the current crop of binoculars. And from what I can see there aren't that many. The "panning doesn't work" hypotheses for instance is IMO plainly false.

Hermann
 
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